AND OXYGEH CONSUMPUON OF NORMAL WEiGHT, UNDERWE‘EGHT, AND OVENEEGHT CGLLEGE WOMEN DUMNG A STANDARMZED WORK TEST IIIIIII II IIIIIIIIII III IIIIIIIIII " 3 1293 01073 9799 Michigan State University A BODY FAT AND OXYGEN CONSUMPTION OF NORMAL WEIGHT, UNDERWEIGHT, AND OVERWEIGHT COLLEGE WOMEN DURING A STANDARDIZED WORK TEST BY Gail B. Glickstein AN ABSTRACT OF A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF ARTS Department of Health, Physical Education, and Recreation 1962 , 'M / / in / law/V: ABSTRACT BODY FAT AND OXYGEN CONSUMPTION OF NORMAL WEIGHT, UNDERWEIGHT, AND OVERWEIGHT COLLEGE WOMEN DURING A STANDARDIZED WORK TEST By Gail B. Glickstein The Problem The purpose of this study was to determine whether there was a difference between normal weight, underweight, and overweight college women in their efficiency to con- vert chemical energy to mechanical energy during a stand- ardized work test. The fat, and fat-free content of 15 normal weight, 15 underweight, and 15 overweight college women were calcu- lated from densiometrically determined specific gravity, and predicted specific gravity. Energy expenditure was obtained under resting conditions, and during low inten- sity steady state work which consisted of a ten minute walk on a motor driven treadmill at two miles per hour on a four per cent grade. Means, standard deviations, medians, and ranges were used for the physical description of the subjects. The F Gail B. Glickstein ratio and "t tests” were used to determine if there were sta— tistically significant differences between the three weight groups. Conclusions From the statistical analysis of the data, the following conclusions were drawn: 1. The mean values for per cent fat in the three weight groups were higher when calculated using the determined specific gravity figures than the mean values for per cent fat when the prediction formula for specific gravity was used. 2. A coefficient correlation of .6722 was found between determined and predicted specific gravity. Energy Expenditure Under Resting Conditions 1. The mean caloric expenditure per hour was largest in the overweight group, and lowest in the underweight group. 2. There were no statistically significant differences between the groups when calories per hour per square meter of surface area was calculated. 3. The analysis of data indicated that the caloric expenditure under resting conditions was dependent upon Gail B. Glickstein body size and when a correction for surface area was made the differences between the three weight groups was reduced to insignificance. Energy Expenditure During Low Intensity Steady State WOrk 1. Significant differences at the .05 level of confidence were indicated between the three weight groups when caloric expenditure per hour per kilogram of body weight was calcu- lated. The results of the "t test" showed that the variance occurred between the overweight and the underweight group. 2. Significant differences at the .01 level of confi- dence were found between the three weight groups when gross caloric cost per kilogram of body weight was computed. The results of the “t test" showed that the variance occurred between the overweight and underweight groups. 3. There was no observable difference in the mean values of the three weight groups when net caloric cost per kilo- gram of body wieght was calculated. 4. The overweight group exhibited the largest mean oxy- gen intake in liters per minute, followed by the normal weight group. The lowest mean value occurred in the under- weight group. The difference between the groups disappeared Gail B. Glickstein when oxygen intake in liters per minute per kilogram of body weight was calculated. 5. The data collected during the low intensity steady state work seemed to indicate that body size influenced the caloric expenditure in the three weight groups. Influence of Fat-free Body weight and Per Cent Fat on Energy Expenditure 1. Significant differences at the .05 level of confi- dence were found between the groups when caloric expenditure per hour per kilogram of fat-free body weight was calculated. The mean values for the groups indicated that the difference occurred between the overweight and underweight groups, and, the overweight and normal weight groups. 2. The caloric expenditure per unit of fat-free body weight during the low intensity steady state work tended to vary with the fat content of the body. 3. As the fat deposition in the body increased it tended to be accompanied by a proportionate amount of fat—free body weight. 4. Overweight and underweight persons do not differ from normal weight persons in their conversion efficiency of chem- ical energy to mechanical energy during a standardized work test. Gail B. Glickstein Recommendations 1. With a large number of women at Michigan State Uni- versity, randomly selected, it would be possible to establish norms for per cent fat in different weight and age groups. BODY FAT AND OXYGEN CONSUMPTION OF NORMAL WEIGHT, UNDERWEIGHT, AND OVERWEIGHT COLLEGE WOMEN DURING A STANDARDIZED WORK TEST BY Gail B. Glickstein A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF ARTS Department of Health, Physical Education, and Recreation 1962 {“3 LN 2‘ -‘ ‘s- t V {J‘ I. 8 DEDICATION Dedicated to my mother and father whose patience, understanding and continuous encouragement made this year possible. ii ACKNOWLEDGMENTS The author wishes to extend sincere thanks to Dr. Janet wessel for her invaluable assistance, and encour- agement in the preparation of this paper. The author is also indebted to Dr. Van Huss for his interest, suggestions, and guidance. Sincere appreciation is extended to: John Ross, David Anderson, and Gunders Strautneiks for their technical assistance. iii TABLE OF CONTENTS Chapter Page I. INTRODUCTION . . . . . . . . . . . . . . . . 1 Purpose of the Study 4 Need for the Study I 4 Definition of Terms 5 Limitations of the Study 9 II. REVIEW OF THE LITERATURE . . . . . . . . . . . 10 Body Composition 10 Energy Expenditure During Standardized Work 23 III. METHODOLOGY . . . . . . . . . . . . . . . . . 38 Subjects 38 Test Procedures and Data Obtained 38 Energy Expenditure Under Resting Conditions 39 Energy Expenditure During Low Intensity Steady State Work . . . . . . . . . . . 4O Anthropometric Measurements 42 Specific Gravity 45 IV. ANALYSIS OF DATA . . . . . . . . . . . . . . . 46 Description of Subjects 46 Per Cent of Standard Weight 50 Specific Gravity and Per Cent Fat 53 Predicted Specific Gravity 53 Determined Specific Gravity 55 Per Cent Fat of Body Weight 55 Comparative Results of Predicted and Determined Specific Gravity 55 Energy Expenditure 61 iv Chapter Energy Expenditure under Resting Conditions Energy Expenditure during Low Intensity Steady State Work Influence of Fat-free Body Weight and Per Cent Fat on Energy Expenditure V. SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS. . . Summary Conclusions Recommendations BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . APPENDIX A. Raw Data on Physical Characteristics of Subjects, Specific Gravity, Per Cent Fat, and Energy Expenditure . . . APPENDIX B. Formulas and Calculations Used To Compute Specific Gravity, Per Cent Fat, Fat-free Body Weight, and Energy Expenditure . . . . . . . . . . . . . Page 61 63 70 74 74 75 79 80 84 109 Table II. III. IV. VI. VII. VIII. IX. XI. LIST OF TABLES Density, Specific Gravity, Per Cent Body Fat. Characteristics of the Subjects . . . . . . . Pound and Percentage Deviation from Standard Weight as Determined by the Pryor WidthAWeight Tables . . . . . . . . . . . . . . . . . . . . Description of Subjects . . . . . . . . . . . . Descriptive Data on Skinfold Fat Measurements . Predicted Body Weight and Per Cent of Standard Weight Calculated on the Basis of the Build and Blood Pressure Study and the Pryor Width- Weight Tables . . . . . . . . . . . . . . . . . Mean Differences in Per Cent Fat of Body Weight Using the Predicted Specific Gravity Formula Based on Per Cent Standard Weight Derived from the Build and Blood Pressure Study and the Pryor Width4Weight Tables . . . . Predicted and Determined Specific Gravity, Per Cent Fat of Body Weight, Kilograms of Fat, Per Cent Fat-free Weight of Body Weight, and Kilograms of Fat-free Body Weight . . . . . . Comparison of Mean Values Obtained from Specific Gravity Measurements in the Young Study with Those in the Present Study . . . . . Correlation Coefficient between Predicted and Determined Specific Gravity . . . . . . . . . . Analysis of Variance of Caloric Expenditure per Hour per Square Meter of Surface Area in the Three Weight Groups . . . . . . . . . . . . vi Page 20 35 46 47 49 51 54 56 59 6O 62 Table XII. XIII. XIV. XVII. XVIII. XIX. XXII. XXIII. Energy Expenditure under Resting Conditions and During Low Intensity Steady State Work. Analysis of Variance of Caloric Expenditure per Hour per Kilogram of Body Weight in the Three Weight Groups . . . . . . . . . . . . . . "t Test" on Caloric Expenditure per Hour per Kilogram of Body Weight in the Three Weight Groups . . . . . . . . . . . . . . . . . . . . Analysis of Variance of Gross Caloric Cost per Kilogram of Body Weight in the Three Weight Groups . . . . . . . . . . . . . . . . . "t Test" on Gross Caloric Cost per Kilogram of Body Weight in the Three Weight Groups . . Caloric Expenditure per Hour per Kilogram of Body Weight and Caloric Expenditure per Hour per Kilogram of Fat-free Body Weight . . . . Analysis of Variance of Calories per Hour per Kilogram of Fat-free Body Weight in the Three Weight Groups . . . . . . . . . . . . . . . . . Raw Data on Physical Characteristics of Subjects . . . . . . . . . . . . . . . . . . . Raw Data on Surface Area, Chest Width and Bi-iliac Width . . . . . . . . . . . . . . . Raw Data on Predicted Body Weight and Per Cent of Standard Weight . . . . . . . . . . Raw Data on Skinfold Fat Measurements . . Raw Data on Predicted Specific Gravity, Per Cent Fat, and Fat-free Body Weight in Normal Group . . . . . . . . . . . . . . . . . . . vii Page 64 65 67 68 69 71 72 85 87 89 91 93 Table XXIV. XXVI. XXVII. XXVIII. XXIX. Page Raw Data on Predicted Specific Gravity, per Cent Fat, and Fat-free Body Weight in Underweight Group . . . . . . . . . . . . . 95 Raw Data on Predicted Specific Gravity, per Cent Fat, and Fat-Free Body Weight in Over- weight Group . . . . . . . . . . . . . . . . 97 Raw Data on Determined Specific Gravity, per Cent Fat, and Fat-free Body Weight in the Three Weight Groups . . . . . . . . . . 99 Raw Data Collected under Resting Conditions . . . . . . . . . . . . . . . . . 101 Raw Data Collected During Low Intensity Steady State Work . . . . . . . . . . . . . 103 Raw Data Collected During Low Intensity Steady State Work . . . . . . . . . . . . . 105 Raw Data Collected During Low Intensity Steady State Work . . . . . . . . . . . . . 107 viii CHAPTER I INTRODUCTION The relatively new field of body composition has posed many interesting questions concerning interrelationships of various body components with the physiological functions, and physical condition of the body. Behnke, one of the early leaders in the field of body composition has emphasized that progress toward a resolu- tion of the relationship between metabolism and weight is greatly aided by the technique of determining accurately in living subjects the fat content of the body.1 Brozek in a recent article has stated, "Body composi- tion is a basic feature of the machinery of the body, and it is to be expected that the existing profound individual difference in body composition will have impact on a vari- ety of biochemical processes and physiological functions 1A. R. Behnke, "The Relation of Lean Body weight to Metabolism and Some Consequent Systematizations," Annals, New York Academy of Science, 56:1098, November, 1953. 2Josef Brozek, "Body Composition,” Science, 134:922, .September, 1961. "The importance of body composition," wrote Williams, "lies in the fact that it is capable of leading the way to— ward a better understanding of human differences." Studies in human difference in physical performance and capacity are not new to physical education. However, with new and more precise methods of measuring and estimating body composition widening research fields are becoming evident. Brozek has focused on the advances in the analysis of human biological individuality, which should facilitate the education of some practical problems of "fitness" concerned with performance capacity and health.4 He also points up the fact that students of body composition should be con- cerned with physical activity as a factor influencing en- ergy metabolism.5 Brozek concluded his remarks with the statement that an examination of the relationship between human physique, body composition, and performance would be most worthwhile. 3 Josef Brozek, "Body Composition," Science, 134:921, September, 1961, citing R. J. Williams, American Scientist, 46:1267, 1958. 4Ibid., pp. 21-22. 5 . Ibld., p. 25. 6Ibid. Energy expenditure in the study of positive caloric balance of overweight, underweight and normal weight women has not been fully clarified. Any question of en— ergy expenditure of women of varying body weights implies a consideration of not only the amount of work done but also of the efficiency of performance. McKee and Bolinger7 postulated that since the princi- ple of conservation of energy expenditure applies to the metabolism of overweight and underweight persons, three possibilities exist as explanations for the excessive accumulation of weight: (1) The ingestion of abnormally large amounts of food; (2) the expenditure of energy in amounts below that of a normal individual; (3) the more efficient conversion of chemical to mechanical energy within the body. Purpose of the Study It is the purpose of this study to investigate the relationship of total body fat of overweight, normal Wallace McKee, and Robert Bolinger, "Caloric Expendi- ture of Normal and Obese Subjects During Standard Test," Journal of Applied Physiology, 15:197, March, 1960. weight, and underweight women to their energy expenditure during low intensity steady state work. These experiments were designed to test the null hy- pothesis that overweight and underweight persons do not differ from normal weight persons in their conversion ef— ficiency of chemical energy to mechanical energy. Need for the Study Data on body composition, efficiency of performance and the work capacity of women of varying weights are scanty although these figures are available for men. There is a paucity of studies investigating the range of body fat of both men and women of varying weights. Basic information in the analysis of human biological individuality can contribute to: (1) understanding of human difference, (2) understanding of fitness, and efficiency of performance, (3) increased effectiveness of guidance procedures in activity programs. Definition of Terms . 8 ngor Width—weight Tables The Pryor Width-weight Tables were used to determine standard weight of the subjects based on sex, age, height, chest width, and bi-iliac width. Overweight, Underweight, Normal weight The degree of overweight, underweight, and normal weight was expressed as a percentage and pound deviation of the actual from the standard weight as seen on the Pryor Width-weight Tables. The mean per cent deviation from standard weight for the overweight group was 24.15, for the underweight group, 16.63, and for the normal weight group, 2.70. Specific Gravity Based on Archimedes' principle, specific gravity is the total weight in air divided by the total body volume. The volume of the body is determined from its displacement of water. The difference between the weight in air and 8Helen Pryor, Width-weight Tables (second edition; Stanford, California: Stanford University Press, 1940), pp. 1-15. the weight completely submersed in water being the weight of the displaced volume of water. Specific gravity = weight in air weight in air — weight in water . . . 9 Predicted Spec1f1c GraVIty Specific gravity was predicted by using the following formula: Specific gravity = 1.0884 - .0004231X — .0003401X 1 13 Where X1 = Skinfold on mid-abdominal line halfway between the umbilicus and the pubis (in mm.) X = percentage ”standard" weight (average weight per height and age. . 0 Per Cent of Fat of Body Weight1 Body fat content was calculated from densiometrically determined specific gravity using the Rathbun and Pace formula: 100(5.548 -——— 5.044) Per Cent Fat = . . . SpelelC graV1ty 9Charlotte Young, Elizabeth Martine, R. Tensuan, and Joan Blondin, "Predicting Specific Gravity and Body Fat- ness in Young WOmen," Journal of the American Dietetic Association, 40:105, February, 1962. 0 l E. N. Rathbun, and N. Pace, "Body Composition I," Journal of Biological Chemistry, 158:675, 1945. Fat-free Body Weight Fat-free body weight was computed by subtracting the calculated fat content from the body weight. Skinfold Thickness (Subcutaneous Fat) By measurement of the skinfold thickness in various sites on the body it is possible to calculate an estimate of the total body fat in a subject. The Lange Skinfold Calipers* were used in this study, calibrated to exert a pressure of 10 gm. per square millimeter of jaw surface. Resting Oxygen Consumption The subject rested in a reclining position for one- half hour after which time a gas mask, valve connection, tubing and Douglas Gas Bags were placed into position. Two ten minute Gas Bags were collected within 2 or 3 min- utes of one another. During the collection phase the sub- ject remained in a reclining position. The gas in the Douglas Bags was immediately analyzed for carbon dioxide and oxygen percentage using the E-Z Oxygen Analyzer, and * werna-Gren Aeronautical Research Laboratory, Kentucky Research Foundation, University of Kentucky, Lexington, Kentucky. the Infrared Carbon Dioxide Analyzer. The gas in the bags was also metered to determine the volume, and temperature. Oxygen Consumption During Low Intensity Steady State WOrk Oxygen consumption was determined during a walk of two miles per hour up a 4 per cent grade for ten minutes. A motor-driven treadmill was used for the walk. Gas collec- tion began when the subject started to walk and two consec— utive five minute Douglas Gas Bags were collected during the 10 minute walk. After the walk the subject immediately sat down for a recovery period of 8 minutes at which time gas was collected in another Douglas Gas Bag. Gas analysis was carried on in the same manner as explained on the pre- ceding page. Limitations of the Study Sample 1. The number of subjects in the sample were limited to forty-five women. 2. The age range included women of college age. 3. A table of random samples was not used in the selection of the subjects. Techniques and Procedures The design of the study was limited in that each of the subjects participating could not follow a definite order or sequence of testing. This was due to a limita- tion in time since all testing for one subject was com— pleted in a morning testing period. Residual air was not collected at the moment of underwater weight. A correction value of 1.022 kg. was used in the formula.11 11 . Charlotte Young, Elizabeth Martine, R. Tensuan, and Joan Blondin, "Body Composition of Young WOmen," Journal of the American Dietetic Association, 38:334, April, 1961. CHAPTER II REVIEW OF THE LITERATURE Body Composition Studies related to body composition have been exten— sively reviewed in the literature. Brozekl has said that the analysis of body composi— tion would provide more meaningful reference criteria for physiological functions than total body weight or surface area. There has been much data gathered on the body compo- sition of men but relatively little data concerned with the body composition of women. The attempts to measure fat in living subjects has obviously been done by indirect means. A number of tech- niques have been used by various investigators. One of the most widely used methods has been the measurement of subcutaneous fat with calibrated skin calipers. However, these measurements not done properly will cause error to occur in the final calculation of total subcutaneous fat. lJosef Brozek, "Body Composition," Science, 134:923, September, 1961. 10 11 Keys and Brozek2 emphasized that a major source of error besides that of positioning and lifting of the skin is the variation in the thickness of the skin. This va— riation is found to be small in comparison with inter- individual differences in the "tela subcut anea." Another problem concerned with correct measurement is the determination of sites on the body. Brozek and Keys3 selected sites if they met certain standardized require— ments: (1)Representation of regions, known to show large variations in subcutaneous fat (abdomen and chest); (2) representation of the extremities (arms and thigh); (3) ease with which the site could be located; and (4) in addition to the requirement of accessibility, the points at which the skinfolds were measured should have a defi— nite location to facilitate in the repetition of the measurement. Garn reporting on fat weight and fat placement in women and men has stated, "The measurement of body fat 2Ancel Keys, and Josef Brozek, "Body Fat in Adult Man," Physiological Reviews, 33:249, July, 1953. 3Josef Brozek, and Ancel Keys, "The Evaluation of Leanness-Fatness in Man: Nbrms and Interrelationships," British Journal of Nutrition, 5-6:204, 1951-1952. 12 relates to two distinct problems, the amount of fat (fat weight),and the distribution of fat (fat-placement).4 Using the roentgenogrammetric technique of measuring sub- cutaneous fat, she obtained data on eighty-one clinically healthy males and females. In seven out of nine fat measurements the women showed higher values. In two sites (deltoid pocket and iliac crest), the male fat thicknesses were absolutely but not significantly greater. The best single predictor of total fat for the male was troch- anteric fat and for the female, iliac crest fat.5 Garn and Gorman6 compared the teleroentgenogrammetric and pinch-caliper techniques of determining subcutaneous fat in men and found a high degree of correlation between the two methods (r = 0.88). 7 . . . . Edwards made some observations on the distribution of subcutaneous fat in women. One hundred and thirty-eight 4 . . . . Marion Garn, "Fat weight and Fat Displacement in the Female," Science, 125:1091, May, 1951. Marion Garn, and Edward Gorman, "Comparison of Pinch— Caliper and Teleroentgenogrammetric Measurement of Subcu- taneous Fat," Human Biology, 28:407-413, December, 1956. 7D. A. Edwards, "Observations on the Distribution of Subcutaneous Fat," Clinical Science, 9:259-270, February— Nbvember, 1950. 13 women of varying degrees of obesity were measured. In order to eliminate some of the random sampling errors in the estimation of total fat he took a large number of measurements. Originally ninety—three sites were chosen and the repeatability of the measurements were estimated. The sites were to be quickly located and easily identi- fied by bony landmarks. After the trial experiments using ninety-three sites, fifty-three points were chosen as having good repeatability. At the time the skinfold measurements were made height and weight were recorded. The actual weight of the subjects were converted to a weight corresponding to a standard height of sixty-four inches so that subjects of different heights could be compared by weight. The measurement values for all sites was summed for each subject. The subjects were then divided into groups according to their converted weight with each group spanning a range of ten pounds. The mean value of the total thicknesses was plotted against the mean value of the corrected weight in each of the groups. A close relationship between subcutaneous tissue thickness and body weight was observed on all fifty-three sites chosen. The data also showed that the l4 thickness of subcutaneous tissue varied from site to site according to a pattern which remained constant over a weight range of 110 to 180 pounds. Skerlj, Brozek, and Hunt8 obtained data on subcutan- eous fat and age changes in body build for eighty-four women whose ages ranged from eighteen to sixty-seven years of age. Ten sites were selected, mainly on the same basis as established by Brozek and Keys.9 For each subject the ten thicknesses were summed and a grand mean calculated. This mean was an estimate of the true mean skinfold thickness for the entire body surface. Edwardslo found that the mean skin thickness is about 1 mm. The authors obtained the thickness of a single layer of sub- cutaneous adipose tissue by subtracting this value from one—half of the skinfold. A correction of 3 mm. was sub- tracted for calculation of the grand mean thickness of 8Bozo Skerlj, Josef Brozek, and Edward Hunt, "Sub- cutaneous Fat and Age Changes in Body Build and Body Form," American Journal of Physical Anthropology, 11:577-599, June-Dec., 1953. 9Brozek, and KEys, loc. cit. OEdwards, loc. cit. 15 skinfold used in obtaining the weight of the subcutaneous fat. The authors did this to compensate for skin thick— ness and for the fact that their average skinfold value was higher than the true average for the body as a whole. The volume of an individual's subcutaneous adipose tissue was obtained by multiplying the grand mean thickness of the adipose tissue by the surface area of the body. The weight of the tissue was calculated by multiplying the volume by 0.94, the approximate density of adipose tissue. weight of the adipose tissue, multiplied by a factor of 0.42 yielded the weight of subcutaneous fat. Total body fat was estimated from specific gravity by the method of Rathbun and Pace.11 The authors presented the two vari— ables that were present in this measurement of subcutan- eous fat from skinfolds. One source of variation was in the thickness of the skin; the average difference sites and interindividual differences at the same site. The compressibility of the skinfold also presented a problem. A second source of error lay in the density of subcutan— eous adipose tissue. The value of 0.94 was used but it was 11E. N. Rathbun and N. Pace, "Body Composition I," Journal of Biological Chemistry, 158:675, 1945. 16 not known whether this value would be constant in both sexes, at all ages, and in all parts of the body. They concluded by stating that with all the possibilities of errors involved in the final calculation it would indi- cate that these measurements were more suitable for group trends than for describing single individuals. Another method used in the estimation of body fat is the calculation of body density and specific gravity from underwater weighing. Keys12 has discussed the basic concept involved which uses specific gravity as a reference in the calculation of the per cent of fat content in the body. Fat will float in water. A cubic centimeter of pure human fat at body temperature weighs 900 milligrams while the same volume of cells weighs 1,060 milligrams, extracellular fluid approximately 1,000 milligrams, and bone mineral about 3,000 milligrams. In the non-fat part of the body, the proportion of cells, extracellular fluid and bone mineral remain fairly constant and therefore the density 12 u ' ' ° Ancel Keys, Body CompOSition and Its Change with Age and Diet," A Collection of Papers Presented At The Weight Control Colloquium (Iowa: Iowa State College Press, 1955). pp. 23-24. 17 of the entire body allows quite a reliable estimate of its fat content. The Archimedian principle has been employed to cal- culate the density of the human body. The weight of a body which is suspended in water is equal to its weight in air less the weight of the volume of water displaced. In order to obtain true density, it is a necessity to measure the total air in the lungs and respiratory pas- sages during the weighing. This measurement yields the true volume of the body, and thus its density is obtained. The measurement of residual air in the subject's lungs at the time of weighing has been a main concern of many investigators. Behnkel3 in surveying this problem has stated that the range of values obtained for residual air is large and therefore, any individual measurement of specific gravity must be accompanied by an actual determination of residual air. 3 l A. R. Behnke, Jr., B. G. Feen, and W. C. welham, "The Specific Gravity of Healthy Men," The Journal of the Amepican Medical Association, 118:496, February, 1942. 18 Brozekl4 considered the concept of body density to be one of vital importance and emphasized that "the method used in the estimation of body fat from specific gravity of the body offers an important advance in the quantita- tive macroscopic morphology of the living man. In liv- ing man the percentage of the body represented by fat estimated on the basis of specific gravity appears to be the best single criterion for characterizing the indi- vidual leanness-fatness."1 There has been insufficient data gathered on density figures for women. Behnkel6 found this to be true and thus estimated a reference value comparable to the index 2.037 he devised for men. The author arrived at a value of 15 per cent fat which corresponds to the 10 per cent value for men. This was an approximation from measure- ments of skinfolds by Edwards.17 l4 Josek Brozek and Ancel Keys, "Evaluation of Leanness- Fatness in Man: Norms and Interrelationships," British Jour- nal oprutrition, 5-6:194-206, 1951-1952. 15 Ibid., p. 195. 16 . A. R. Behnke, "The Relation of Lean Body weight to Metabolism and Some Consequent Systematizations," Annals, New York Academy of Science, 56:1105, Nev., 1953. 7 Edwards, loc. cit. l9 Young18 and her associates reported a pilot study. designed to obtain normative data on the lean body mass and fatness of a representative sampling of ninety—four young women. The authors were interested in studying the interrelationships existing between estimates of lean body mass and/or adiposity based on determination in each of body density, total body water, skinfold measurements, fat-pad measurements from soft tissue x- rays, anthropometric measures, creatinine excretion and basal oxygen consumption. The subjects selected for their study were healthy women attending Cornell Univer- sity: Their findings on density, specific gravity and percentage of fat content-in the body are presented in Table I, which appears on the following page. The authors further stated that among skinfold measure- ments, the best correlation with total skinfold thick— ness and with density was for sites on the lower trunk, particularly the pelvic region. 0f the upper trunk measurements, that over the lower ribs gave the best 18Charlotte Young, "Body Composition of Young WOmen," Journalyof the American Dietetic Association, 38:332-340, April, 1961. ‘ . 4 20 . . . 19 Table I. Density, speCific graVity, per cent body fat Characteristic Range Mean S.D. Median Density (gm./cc.) 1.0150— 1.0342 0.0094 1.0343 1.0595 Specific gravity 1.0217— 1.0408 0.0094 1.0411 1.0665 Per cent body fat 15.81- 28.69 4.856 28.55 (Rathbun-Pace) 38.62 correlation with both total skinfold thickness (r = 0.8883) and density (r - 0.6110). Of all measures used, body den- sity was most highly correlated with skinfold thickness (r = -0.6766); next was basal oxygen consumption expressed on a per kilogram basis (r = 0.6001). Young and her associates20 in a more recent article' published a predictive equation for specific gravity. Intercorrelations between skinfolds, with total skinfold 19Ibid., p. 335. 20C. Young, E. Martin, R. Tensuan, and J. Blondin, 'Tredicting Specific Gravity and Body Fatness in Young WOmen," Journal of the American Dietetic Association, 40:102-107, February, 1962. 21 thickness and with density, were obtained. Using the skinfold measurements obtained in their earlier study?1 linear regression equations were formulated to predict specific gravity. After numerous computations, the authors found that when a standard weight was included as a variable, there was no significant difference in predicting specific gravity with using only one skin- fold. The pubis skinfold used in this formula had the best correlation with both total skinfold thickness (r = 0.8883) and density (r = 0.6110) as reported in the previous study. The following equation was formu- lated for predicting specific gravity.22 SpeCific graVity = 1.0884 —.000423lx1 -.0003401x13 When X1 = skinfold on the mid-abdominal line halfway between the umbilicus and the pubis (in mm.) X = percentage "standard" weight (average weight per height and age) The correlation between determined and predicted specific gravity based on this equation was 0.6990; 1 Young, et al., loc. cit. 22YOung, et al., op. cit., p. 105. 22 standard deviation of differences was 0.0068 units. This was found to be approximately 3.4 per cent body weight as fat. Energy Expenditure During Standardized werk Many researchers have been aware of weight and body size as a factor influencing energy expenditure in physi- cal activities. Body size as related to metabolism has been discussed extensively in the literature and con- flicting reports exist regarding the efficiency of energy expenditure in obese persons. Wang, Strouse, and Morton23 investigated the mechan- ical efficiency of obese women as compared with that of normal and underweight subjects. Twenty-seven obese women whose weights ranged from 60.9 to 118.6 kg. par- ticipated in a series of forty—one experiments. Nine normal, and seven underweight women were selected for comparison. Their respective weights ranged from 48.3 23 C. C. Wang, Solomon Strause, and Zelma Morton, "The Metabolism of Obesity: V Mechanical Efficiency," Archives of Internal Medicine, 45:727-723, Jan.-June, 1930. 22 standard deviation of differences was 0.0068 units. This was found to be approximately 3.4 per cent body weight as fat. Energy Expenditure During Standardized Work Many researchers have been aware of weight and body size as a factor influencing energy expenditure in physi- cal activities. Body size as related to metabolism has been discussed extensively in the literature and con- flicting reports exist regarding the efficiency of energy expenditure in obese persons. wang, Strouse, and Morton23 investigated the mechan- ical efficiency of obese women as compared with that of normal and underweight subjects. Twenty-seven obese women whose weights ranged from 60.9 to 118.6 kg. par- ticipated in a series of forty-one experiments. Nine normal, and seven underweight women were selected for comparison. Their respective weights ranged from 48.3 23 C. C. Wang, Solomon Strause, and Zelma Morton, "The Metabolism of Obesity: V Mechanical Efficiency," Archives of Internal Medicine, 45:727-723, Jan.-June, 1930. 23 to 63.2 kg. and from 40.0 to 51.3 kilograms. All sub— jects received practice on the bicycle ergometer before the experiment actually started. Measurement of heat production was taken while the person sat on the ergometer and while riding with a load of 2.7 kg. at a speed of about 12 revolutions per min- ute. Ten minutes was allotted to the first part of the test and three to eight minutes for the ride. The ex- periment was not carried to the recovery stage. The en- ergy expenditure for sitting on the ergometer was higher in the obese subjects than in the other two groups. The authors found that the mechanical efficiency varied in- versely with the percentage overweight. The average values for the three groups were 21.7, 24.4 and 27.6 per cent. A gradual decrease in mechanical efficiency with an increase in obesity was observed in the obese group. The average energy expenditure per kilogram of body weight was 0.932 in the overweight group, 1.072 in the normal group and 1.279 in the underweight group. The authors concluded that the higher values of the obese group was undoubtedly due to the increased load of these subjects as shown by the average energy expenditure. 24 McKee, Bolinger24 determined the energy expenditure of twenty-five normal and nineteen obese persons during the basal state and during a standard work test. The standard work test involved the pulling of weights by the countertrained right arm. The authors designed the test to determine if obese persons differed from normal persons in their efficiency during a standard exercise test. The weights of the obese subjects were greater than 110 per cent normal as predicted by the Metropoli- tan Life Insurance Statistic Bulletin. The authors found that the total caloric expenditure of the obese person was higher for the standard work test but that this increase was due to the increased basal expendi- ture of energy rather than to an increase in the energy used to perform the actual work. Therefore, the over- all efficiency was actually not decreased in obesity and could not be considered as an important factor in the unfavorable caloric balance of the obese person. 24 . . . W. McKee, and R. Bolinger, "Caloric Expenditure of Normal and Obese Subjects During Standard work Test," Journal of Applied Physiology, 15:197-200, March, 1960. 25 Keys25 reviewed the concept widely held by others when he emphasized that it would seem that body size is of utmost importance with regard to both basal metabolism and the cost of muscular activity. It is found that the energy cost of moving the body (or its parts) is directly proportional to the weight of the body, namely in such activities as walking. Some investigators, however, have been concerned with the apparent lack of data relating body components to energy metabolism. Seltzer25 measured the oxygen uptake of thirty-four males age twenty to twenty-four during moderate exercise. The subjects walked on a treadmill up a grade of 8.6 per cent at 5.6 km./hr., for 15 minutes. Seltzer found that in moderate exercise oxygen consumption correlated least with chest circumference (0.817), then with weight (0.771) and surface area (0.724) and only very roughly with other 5 American Medical Association, Handbook of Nutrition (2nd ed.) (New York: Country Life Press Corporation, 1951), p. 266. 26Carl Seltzer, "Body Build and Oxygen Metabolism at Rest and During Exercise," American Journal of Physiology, 129:1-13, April, 1940. 26 physical measurements. The author calculated the mechanical efficiency of 44 different anthropometric groups within the wide sample. The lowest figure for the efficiency of any group was 15.0 per cent and the highest 16.1 per cent. On the basis of his data the author stated that in moderate exercise those whose body build was "lateral" rather than "linear” have the greatest mechanical efficiency. Mahadeva, Passmore, and wolk27 studied the effectszi of food, age, sex, and race on metabolism during mus- cular activities. Forty-six male subjects walked for 10 minutes on an indoor track at a uniform speed of 3 miles per hour. The subjects also performed a stepping test and then caloric expenditure during resting, step- ping and walking was calculated. The authors found that of all the varaiables studied, weight was the most im- portant factor, in energy metabolism. . . 28 Erickson, Simonson, Taylor, Alexander, and Keys experimented with a group of men walking on a treadmill. 27K. Mahadeva, R. Passmore, and B. Woolf, "Individual Variations in the Metabolic Cost of Standardized Exer- cises: The Effects of Food, Age, Sex, and Race," American Journal of Physiology, 121:225-231, July-September, 1953. 28L. Erickson, E. Simonson, H.L. Taylor, H. Alexander, and A. Keys, ”The Energy Cost of Horizontal and Grade Walk- ing on the Motor-Driven Treadmill," American Journal of Physiology, 145:391-401, Nevember-March, 1945-46. 27 The forty—seven male subjects participating in the ex- periment walked at a speed of 3.5 mph up a 10 per cent grade. It was found that when oxygen consumption was related to the body weight to express walking efficiency, this procedure removed the percentage variability in a group of men with a wide range of body weight. Passmore, and Durnin29 measured 50 persons walking under standard conditions at 4.8 km./hr. (3 mph) and found the energy expenditure proportional to body weight. Von Dobeln3O investigated the relationships betweenw’ maximal oxygen intake, total hemoglobin, and (body weight minus adipose tissue)n. In all, 33 male and 32 female subjects participated in the study. For each subject, total hemoglobin, per cent fat based on hydrostatic weighing, and maximal oxygen consumption per unit of time was obtained. Maximal oxygen intake values were plotted against the respective values for body weight minus adipose 29 R. Passmore, and J.V.G.A. Durnin, "Human Energy Expenditure," Physiological Reviews, 35:801-840, Jan.- Oct., 1955. 30 . . Wilhelm Von Dobeln, "MaXimal Oxygen Intake, Body Size, and Total Hemoglobin in Normal Man," Acta Physiolog- ica Scandinavica, 38:193-99, Sept., 1957. 28 tissue. A correlation coefficient of 0.756 i 0.053 was reported between (weight minus adipose tissue) 2/3 and maximal oxygen intake. Buskirk, and Taylor31 studied the relationships be-i’ tween maximal oxygen intake and components of body com— position. Fifty-nine young college students and soldiers participated in the experiment. The following correla- tion coefficient were obtained: maximal oxygen intake with body weight, 0.63; maximal oxygen intake with "active tissue," 0.91. The authors stated that the best unit of reference for the maximal oxygen intake was "active tis— sue." They defined "active tissue" as body weight minus estimated body fat (densitometry), thiocyanate space and bone mineral (7% of fat-free weight). The subjects were also divided into three groups of nine relatively seden- uflqrstudents, classified according to the percentage of body fat (less than 10, 10-25, and 25 and above). Each group was compared with respect to the maximal amount of oxygen used/ min./kg. of fat-free body weight. The 31 . . . E. Buskirk, and H. Taylor, "Relationships Between Maximal Oxygen Intake and Components of Body Composition," Federation Proceedings, 13:21, March-December, 1954. 29 authors found no observable difference existing between the groups and concluded that, "Obesity in relatively sedentary young men fails to interfere with performance of the combined respiratory-cardiovascular system as . . 32 measured by the maXimal oxygen intake.” Miller and Blyth33 presented a report which testedt” their hypothesis that "variations in body type and body composition might significantly influence the metabolic cost of work per unit of body weight and that, as a re- sult, some other unit than weight might better predict the metabolic cost of work."34 Thirty healthy male col- lege students with wide ranges of body type and fat con- tent were selected for the study. weights ranged from 55.0 to 130.9 kg., and calculated fat content ranged from 0.0 to 33.9 per cent. Each subject walked on a motor- driven treadmill at 5 mph up a 10% grade for 15 minutes. Body fat content was calculated from densiometrically determined specific gravity and corrected for residual air 321bid., p. 21. 33 . A. T. Miller, and C. S. Blyth, "Influence of Body Type and Body Fat Content on the Metabolic Cost of Work,” Journal of Applied Physiology, 8:139-140, July—May, 1955- 1956. 34Ibid., p. 139. volume. was used to calculate fat content from specific gravity. The follow— ing correlation coefficients were found: . . . 3 Correlation CoeffiCient Item correlated r p Exercise'O2 X Weight 0.75 0.01 Exercise 02 X Surface Area 0.71 0.01 Exercise 02 X Lean Body Mass 0.67 0.01 Exercise 02 X Per Cent Fat 0.52 0.01 Exercise 02/kg. X Per Cent Fat -0.23 N.S. Exercise 02/kg. X weight -0.16 N.S. Exercise 02/kg. L.B.M. X weight 0.36 0.05 Exercise 02. Kg. L.B.M. X Per Cent Fat 0.43 0.05 Per Cent Fat X weight 0.80 0.01 Per Cent Fat X Lean Body Mass 0.32 0.10 Lean Body Mass X weight 0.82 0.01 Miller and Blyth stated that their findings were in 5‘ 30 The formula of Rathbun and Pace35 37 complete agreement with those reported by Mahadeva et al., in indicating that the metabolic cost of moving and lifting the body can be predicted from body weight alone. 35Rathbun and Pace, loc. cit. 36Miller and Blyth, op. cit., p. 140. 3 7Mahadeva, Passmore and Woolf,op. cit., p. 230. 31 From the data obtained in their study the authors presented the following conclusions: 1. The metabolic cost of lifting the body is directly" proportional to gross body weight, and the cost of work per unit of body weight is only slightly in- fluenced by height and fat content. The correlations between metabolic work cost and" height, lean body mass, chest circumference are reduced to insignificance when the influence of weight is eliminated. On the other hand, the cor- relation between metabolic work cost and weight remains highly significant when the separate in- fluences of height, fat content, and lean body mass are eliminated. It is therefore suggested that gross body weight is the best metabolic ref- erence unit for expressing the cost of work in- volving lifting the body weight. Although predic— tion accuracy between body weight and surface area, the former is preferable because it is a simpler unit. As the body fat content increases, the exercise 02:9 requirement per unit of lean body mass also in- creases. This result could, of course, be pre- dicted from the correlation between weight and exercise 02 requirement, and is in contrast with the virtual lack of influence of fat content on the basal 02 consumption per unit of lean body mass. There is a barely significant correlation between *‘ per cent fat and kilograms of lean body mass. This may be interpreted as indirect support for the claim that the deposition of fat is accompanied by the addition of a definite proportion of lean body mass tissue.38 38Miller and Blyth, op. cit., p. 139. 32 Miller and Blyth reviewed Buskirk and Taylor39 work on maximal consumption and body composition. The authors stated they "would warn against a possible implication that obesity is without effect on the capacity for exer- cise, at least of the type which involves lifting the body. If obesity increases the energy requirement of exercise without a corresponding increase in maximal 02 uptake capacity, it definitely is limiting. we have previously reported that the basal 0 consumption per 2 unit of lean body mass is relatively constant despite the wide variations in body fat content. This fact, consider- ed in conjunction with the data in the present report in- dicating a direct relation between fat content and 02 con- sumption per unit of lean body mass during work, suggests that the "cardiovascular burden" imposed by obesity is ~ minimal at rest and is clearly manifested only during 1 physical exertion. . . . 4 . welch, Riendeau, Crisp, and Isenstein, 1 studied the w” relationship of maximal oxygen consumption to various 9Buskirk, and Taylor, loc. cit. 40 Miller and Blyth, op. cit., p. 140. 41B. E. welch, R. P. Riendeau, C. E. Crisp, and R. S. Isenstein, "Relationship of Maximal Oxygen Consumption to Various Components of Body Composition," Journal of Applied Physiology, 12:395-98, May, 1958. 33 components of body consumption in twenty-eight healthy young men. The authors stated that on the basis of previous studies conducted by Taylor and Buskirk,42 and Von Dobeln,43 the assumption was that oxygen was more highly related to lean tissue than to any other des- cription of body composition. "One can infer from the correlations reported that maximum oxygen consumption is dependent mainly on the amount of lean tissue in the body.44 The subjects used in this study were tested on thed‘ treadmill at grades of 6, 8.5 and 11 per cent. The time of the runs were 2 minutes and 45 seconds. Maxi— mal oxygen consumption was reached when running at the next higher grade did not increase the maximal 02 con— sumption more than 150 cc. above the previous grade. Significant correlations (P 0.01) between maximal oxy- gen consumption in liters per minute and body weight (0.59); body weight minus fat (0.65); and body weight 2Taylor and Buskirk, loc. cit. 3Von Dobeln, loc. cit. 44 . . . welch, Riendeau, Crisp, and Isenstein, loc. cit., p. 395. 34 minus fat minus bone (0.64) were obtained. The authors; emphasized that the correlations obtained by Taylor and Buskirk,45 and Von Dobeln46 can be interpreted in that from 53 to 83% of the variability in maximal oxygen con— sumption may be attributed to variations in the percent- age of lean body mass. welch and his associates conclu— ded that the percentage of fat in the body had no signi- ficant influence on the maximum 02 consumption when ex- pressed as either liter per minute or cubic centimeters per minute per kilogram of fat-free body weight. Sig— nificant differences were found when maximum oxygen con- sumption was expressed as cubic centimeters per minute per kilogram of body weight. The authors suggested that although fat may not have an effect on the ability of the tissues to extract oxygen, it did have a significant ef- fect on the circulatory capacity of the individual. This was due to the fact that fat increased weight and there- fore, the energy requirement. However, there is not a corresponding increase in the maximum oxygen intake. 5 Taylor and Buskirk, loc. cit. 46Von Dobeln, op. cit., p. 196. 35 Johnston and Bernstein47 undertook an investigation of the body composition and oxygen consumption of over— weight, normal and underweight women. They investigated the relationship of the percentage of fat in these women and also the rate at which their “cell mass,‘ consumed oxygen. Body composition was determined from total body water and extracellular water. 4 Table II. Characteristics of the subjects 8 fi j Age 21 - 59 Total Body weight Kg. 39.8 - 186.4 Kg. Body Fat 6.7 - 88.4 Per Cent of Body weight 16.9 - 57.2 Lean Body Mass kg. 33.0 - 98.1 Per Cent of Body weight 42.7 - 83.1 Cell Mass kg. 19.7 - 68.4 Per Cent of Body weight 31.3 - 59.7 Basal 02 Consumption ml./min. 140 - 357 Basal 0? Consumption ml./sq.m/min. 85 — 136 47 L. Johnston,and L. Bernstein, "Body Composition and Oxygen Consumption of Overweight, Normal and Underweight women," Journal of Laboratory and Clinical Medicine, 145: 109-118, Jan.-June, 1955. 48Ibid., pp. 111-112. 36 The data obtained showed that the constituents of the lean body mass remained constant in proportion throughout the weight range and that fat was the greatest independent variable. They also found that as the percentage of standard weight increased both lean body mass and the cell mass remained equally and highly correlated with the ex- panding surface (0.92). This caused the oxygen consump- tion to remain equally well correlated with the subjects' surface area (0.91), lean body mass (0.94), and cell mass (0.92). Astrand49 tested forty-two female subjects on the treadmill. The women walked at a fixed speed of 5 km./hr. (3.1 miles/hr.) on the level for about 12 minutes. The women's ages ranged from 20 to 65 and their weight from 56.2 kg. to 65.4 kg. Oxygen uptake per kg. body weight was, for all subjects on the average 15.8 i 0.33 ml. The oxygen intake averaged 0.96 l./min. and the maximum oxygen uptake was 2.02 1./min. Astrand,in discussing her results, stated that in walking, running or on a step test greater amounts of 49Irma Astrand, "A Pilot Study of Work on a Treadmill in Women 20-65 Years," Acta Physiologica Scandinavica, 49: 61-62, July 1960. 37 energy were required as body weight was increased. This will hold true if the skill level was the same. "This is clearly evident where the oxygen uptake is higher in the two oldest age groups est. From the equalizing tion to CO2 ml./kg. it is depends upon a difference 50Ibid., p. 62. as compared to the two young- brought about by a recalcula— evident that this difference in body weight."50 CHAPTER I I I METHODOLOGY To determine the per cent of total fat in overweight, and underweight college women and its relationship to work efficiency during low intensity steady state work, the following methods and procedures were followed. Subjects The sample for this study was selected in the fall and winter semesters from a group of college women at— tending service classes in physical education at Michigan State University. The majority of the women were fresh- men whose ages ranged from 17 to 21 years of age. Sus- pected overweight, and underweight women were listed on a sheet and given to the author by the instructors of the service classes. IThe ages, heights, weights, and Pryor measurements1 were then taken in a preliminary testing period. These measurements together with the height, weight, and age to the nearest birthday were then lHelen Pryor, Width—weight Tables (second edition; Stanford, California: Stanford University Press, 1940), pp. 1-15. 38 39 plotted on the Pryor Chart to determine per cent and pound deviation from normal, and also, per cent of standard weight. Nermal weight subjects were selected by the author and identical measurements were made in a preliminary testing period. The women were placed in two groups in accordance with their measurements. There were 15 subjects in each group making a total of 45 subjects for the study. Test Procedures and Data Obtained Data collection covered a period of approximately four months. Measurements on each subject were com- pleted in one testing period of approximately 3-4 hours in length. Morning hours from 8:00 o'clock to 12:00 o'clock on three week days were used as testing periods. Energy Expenditure under Resting Conditions Data on resting metabolism was gathered in the morn- ing hours. The subject rested in a reclining position for one—half hour after which time a full-face gas mask was placed on the subject. The face mask was connected to tubing and valve connection which lead to a Douglas 40 Gas Bag. Two ten minute gas samples were obtained within 2-3 minutes apart. The samples were then imme- diately analyzed for carbon dioxide and oxygen content using the E.Z. Oxygen Analyzer and the Infrared Carbon dioxide Analyzer. The gas in the bags were also metered to determine temperature and volume. Calculations were made based on percentage of oxygen and carbon dioxide in the bags. Temperature corrections were made on the gas being metered through the Kofranyi meter. Energy Expenditure During Low Intensity Steady State WOrk Immediately after collection of resting gas the sub- ject proceded to the treadmill at which time the follow- ing procedure was followed: 1. The subject wore a face mask which had connecting tubing to a Douglas Gas Bag and valve connections. 2. The subject walked for ten minutes at a uniform speed of two miles per hour up a four per cent grade. Collection of gas began at the start of the walk and continued for five minutes. At the end of the first five minutes the valve was switched so that a second Douglas Gas Bag col- lected the last five minutes of walking. 41 3. At the completion of the ten minute walk, the subject immediately sat down on a chair placed on the treadmill. The valve was switched again so that the gas expired during the eight minute recovery period was collected in another Douglas Gas Bag. The entire testing period was timed using a stop watch. The three gas bags were immediately analyzed for carbon dioxide and oxygen content using the E-Z Analy- zer and Infrared Carbon Dioxide Analyzer. Ventilation was determined by metering the gas and obtaining volume and temperature. The following information was obtained: (1) (2) (3) (4) (1) (2) (3) (4) (5) Energy Expenditure under Resting Conditions ca1./hr. cal./hr./kg. body weight cal./hr./square meter of surface area 02/l./min. Energy Expenditure During Low Intensity Steady State werk cal./hr./kg. body weight cal./hr./kg. fat-free body weight gross caloric cost/kg. body weight net caloric cost/kg. body weight oxygen/liters/min. 42 (6) oxygen/liters/min./kg. body weight (7) ventilation (8) gross oxygen debt (9) net oxygen debt (10) exercise R.Q. (11) recovery R.Q. Anthropometric Measurements The procedure followed for these measurements were taken from the instructions issued by the Committee on Nutritional Anthropometry of the Food and Nutrition Board of the National Research Council. Height The subject removed shoes; stood with her back against the calibration on the stadiometer; heels, hips, shoul- ders and head were touching the backboard. The head was erect with the chin tucked in slightly. The subject stood as tall as possible. The square was placed against the calibration on the backboard above the head of the sub- ject. It was brought down until it fitted firmly against the top of the subject's head. The reading was taken at the lower edge of the square. Height was recorded to the nearest one—half centimeter. Committee on Nutritional Anthropometry of the Food and Nutrition Board, Nutritional Research Council. In Body Measurements and Human Nutrition. J. Brozek, ed. (Detroit: Wayne University Press, 1956). 43 weight The subjects were weighed without shoes in standardized dress of shorts or bermudas, cotton blouse and socks. weight was recorded to the nearest half-kilogram. Skinfold Meagprements The skinfolds were grasped between the thumb and index finger. The size of the fold was enough to include two thicknesses of skin and subcutaneous fat but no muscle or fascia. The application of the Lange Calipers* was about 1 cm. from the fingers and at a depth approximately equal to the thickness of the fold. Three successive measurements were taken at each site. Measurements were taken on the right side of the body. All folds were taken in the vertical plane except for the measurement near the scapula which was taken diagon- ally. The measurement in mm. was recorded. The following sites were measured: 1. Uppeijrm Skinfold (Triceps). The skinfold is located * werna-Gren Aeronautical Research Laboratory, Kentucky Research Foundation, University of Kentucky, Lexington, Kentucky . 44 at the back of the right upper arm (over the triceps), at the level midway between the tip of the acromial process of the scapula and the tip of the elbow. The level is located with the forearm flexed at 90°. In making the skinfold measurement the arm hung down freely and the skin- fold was lifted parallel to the long axis of the arm. 2. Scapulg; Skinfold. The skinfold is located below the tip of the right scapula. 3. ‘ngpp, The skinfold is located on the waist on mid- axillary line, half-way between the lower rib and the iliac crest. 4. gmpilicus Abdompp, The skinfold is located just to the right of the umbilicus (one-third the distance from the umbilicus to the iliac crest). 5. Lower Ribs. The skinfold is located on the lateral aspect of the thorax over the lower rib midway between the axilaa and the iliac crest. 6. PgQig, The skinfold is located on the mid-abdominal line halfway between the umbilicus and the pubis. I The waist, umbilicus, abdomen, lower ribs, and pubis skinfold measurements were taken with the subject in a supine position. 45 Specific Gravity Appointments for under water weighing were not made with the subjects during and ten days prior to menstruation to avoid the measurement of excess fluid in the body. On the testing day the subject was seated in a steel chair which was suspended from a strain gauge. The subject was instructed to tie herself securely in the chair to avoid floating away from the chair while under water. A Sargent Recorder and Sanburn Recorder were used to record the measurement under water. A short period of orientation preceeded the actual measurement. During this time familiarity with the equip- ment (nose clip and mouth-piece) and description of the procedure was established. The subject was then placed under water until she was completely submersed at a pre- determined depth. The subject then followed the previous instructions to inhale and exhale forcibly all the air from the lungs. The position of exhalation was held steady for at least 10 seconds during which time data was ob- tained on the graph. After resuming normal breathing the procedure was repeated until three to four measurements were obtained. CHAPTER IV ANALYSIS OF DATA Description of Subjects Subjects were placed into groups according to the pound and percentage deviation from standard weight as determined by the Pryor Width4Weight Tables.1 The means, standard deviations, medians, and ranges for the three weight groups are presented in Table III. Descriptive information on the normal, underweight, and overweight groups will be found in Tables IV and V. Table III. Pound and percentage deviation from standard weight as determined by the Pryor Width4Weight Tables Characteristics Mean S.D. Median Range Normal Weight Lb. deviation 5.26 3.439 5.9 0.1 9.7 % deviation 2.70 2.867 2.18 0.0 6.7 Underweight Lb. deviation 21.55 6.675 20.1 14.8 37.7 ‘% deviation 16.63 4.033 15.4 12.7 26.4 Overweight Lb. deviation 35.52 12.572 34.5 19.5 58.7 % deviation 24.15 8.337 23.0 14.5 39.9 lHelen Pryor, Width4Weiqht Tables (second edition; Stanford University Press, Stanford, California: 14. 46 1940), p. Table IV. Description of subjects j NORMAL WEIGHT* Characteristics Mean S.D. Median Range Age (years) 18.62 .419 18.6 18.03 19.11 Height (inches) 65.46 1.303 65.94 62.99 67.13 " (cm.) 166.26 3.302 167.50 160.0 170.5 Weight (lbs.) 129.93 8.828 133.1 114.2 143.5 " (kg.) 59.06 4.026 60.48 51.92 65.22 Width--chest (cm.) 26.75 1.454 26.6 25.0 - 29.7 " bi-iliac (cm.) 28.37 1.361 28.3 26.0 - 31.1 Surface area (sq. meters) 1.653 .0693 1.67 1.53 - 1.75 *Calculated on the basis of 15 subjects in each group. 48 UNDERWEIGHT* OVERWEIGHT* Mean S.D. Median Range Mean S.D. Median Range 18.67 .546 18.6 18.1 - 18.56 .381 18.6 18.1 — 19.7 19.4 65.49 2.965 66.73 61.02 64.44 2.48 63.90 60.43 - 69.88 68.50 166.33 7.528 169.0 155.0 - 163.96 6.285 172.3 153.5 - 177.5 174.0 107.12 12.18 105.3 88.2 - 179.41 17.58 180.2 141.5 - 131.2 205.7 48.68 5.532 47.86 40.10 - 81.54 8.035 81.90 64.30 - 59.64 93.50 25.62 1.718 25.7 22.3 - 29.94 2.332 30.2 25.2 - 29.4 35.5 27.13 2.045 27.2 23.9 - 30.35 1.709 30.8 27.3 - 30.1 33.5 1.523 .113 1.55 1.33- 1.875 .102 1.87 1.67- l.69 2.02 Table V. Descriptive data on skinfold fat measurements NORMAL WEI GHT* Site of Skinfold (Mm.) Mean S.D. Median Range Triceps 16.79 4.196 17.6 7.0 - 25.0 Scapula 11.63 3.286 10.0 8.3 — 18.6 Lower ribs 13.41 4.301 13.0 8.0 - 20.6 Waist 14.93 3.579 14.6 9.0 — 21.0 Umbilicus 17.87 4.680 17.3 7.3 - 28.0 Pubis 32.49 2.948 33.0 16.0 - 45.0 Sum 107.19 7.119 105.8 65.2 - 140.2 *Calculated on the basis of 15 subjects in each of the groups. 49 UNDERWEIGHT* OVERWEIGHT* Mean S.D. Median Range Mean S.D. Median Range 10.7 3.945 10.6 4.6 - 32.61 6.419 31.6 23.0 18.0 44.0 8.41 2.142 7. 6.3 - 27.72 8.095 27.2 16.0 12.6 45.3 7.68 1.540 7. 5.0 - 34.6 10.5 35.6 14.3 10.6 48.6 10.81 3.85 10.6 4.0 - 34.51 9.229 34.0 21.0 19.0 47.3 13.76 2.768 15.0 7.3 - 35.48 8.668 33.6 22.3 17.3 53.0 24.73 9.056 25.3 5.6 - 52.98 6.62 53.3 47.0 38.2 60.6 76.14 17.885 78.4 48.8 - 217.9 43.085 222.1 147.1 - 105.7 292.5 50 Per Cent of Standard Weight Per cent standard weight was calculated by dividing the predicted weight into the actual weight. The predicted weights were obtained from the Pryor Width4Weight Tables,2 and also from the Build and Blood Pressure Study.3 The standard weight figures in the Build and Blood Pressure Study included shoe heel height of about two inches and usual indoor clothing, which for women approxi- mate four to six pounds. In order to make the figures in this study as comparable to these as possible, the average heel height of one inch was added to each height and two pounds were added to the weight to cover the extra clothing. As reported in Table VI the mean difference in pre— dicted weight for the normal group was 3.4 pounds with a mean difference of 2.47 units for per cent standard weight. The same figures for the underweight group were 2.27 pounds and 2.11 units in per cent standard weight. The overweight group showed the largest variation between the two means with 16.89 pound difference in predicted weight and a 17.31 unit difference in per cent standard weight. ZIbid. 3Build and Blood Pressure Study, 1959, Vol. I (Chicago: Society of Actuaries, 1959). 51 Table VI. Predicted body weight and per cent of standard weight calculated on the basis of the Build and Blood Pressure Study and the Pryor Width-Weight Tables NORMAL WEI GHT Characteristics Mean S.D. Median Range Actual weight 129.92 8.828 133.1 114.2 - 143.5 Pryor Width-Weight Tables Predicted weight 134.06 8.939 133.0 122 - 144 Per cent standard 96.81 3.782 96.24 92.85 - 106.75 Build and Blood Pressure Study: Predicted weight 130.66 4.369 132 122 - 136 Per cent standard 99.38 5.01 99.26 90.63 - 108.71 52 UNDERWEIGHT OVERWEIGHT Mean S.D. Median Range Mean S.D. Median Range 107.12 12.18 105.3 88.2- 179.41 17.58 180.2 141.5— 131.2 205.7 128.66 14.7 129 103- 143.89 9.24 146 122- 151 156 83.38 4.07 84.59 73.64- 124.64 8.49 123.5 114.53- 87.29 139.93 130.93 13.58 136 111- 127.00 9.30 126 111— 149 142 81.27 6.798 78.17 72.43- 141.95 17.38 139.85 115.98- 96.25 169.55 53 The larger variation in the overweight group might have been caused by the difficulty which the examiner experienced in measuring the bi-iliac width of the subjects to obtain the predicted weight from the Pryor Width—Weight Tables. Specific Gravity and Per Cent Fat Predicted Specific Gravity Predicted specific gravity was obtained by the use of the prediction formula devised by Young and her associates. The pubis skinfold measurement and the per cent of standard weight were the two variables used in this formula. The figures for the per cent standard weight were based on the predicted weight for age and height as determined by the Build and Blood Pressure Study. A comparison was made in this study between the per cent fat of body weight obtained using the per cent standard weight derived from the predicted weight in the Build and Blood Pressure Study and that obtained from the Pryor Widty- Weight Tables. The mean differences are presented in Table VII. 4Charlotte Young et al., "Predicting Specific Gravity and Body Fatness in Young Women," Journal of the American Qietetic Association, 40:105, February, 1962. 54 Table VII. Mean differences in per cent fat of body weight using the predicted specific gravity formula based on per cent standard weight derived from the Build and Blood Pressure Study and the Pryor Width—Weight tables Groups Mean S.D. Median Range Normal .759 .4295 .73 .15 - 1.54 Underweight .842 .6255 .90 .00 - 2.07 Overweight 3.081 1.990 2.93 .00 — 2.07 As indicated in Table VII the use of the two different figures for per cent standard weight in the prediction formula did not alter to any considerable extent the per cent fat of body weight in each weight group. The normal weight group and underweight group showed less than a one per cent difference in the per cent fat of body weight while the overweight group showed a three per cent fat difference. On the basis of this data it was decided to use the predicted standard weight obtained from the Build and Blood Pressure Study so that the resulting data could be compared with the data found in the Young study. 55 Determined Specific Gravity Determined specific gravity was obtained by the method of underwater weighing. The correction value for residual air was secured by using the mean value of 1.022 kg. ob- tained in the Young study on ninety-four young college women . Per Cent Fat of Body Weight Per cent fat of body weight was derived from the Rath- bun and Pace formula using specific gravity figures. Comparative Results of Predicted and Determined Specific Gravity Presented in Table VIII are the means, standard devia- ‘tions, medians, and ranges obtained for predicted and determined specific gravity. Calculations based on speci- fic gravity figures and per cent fat were made for kilograms of fat, per cent fat-free body weight, and kilograms of fat- free body weight. 5Charlotte Young et al., "Body Composition of Young Women," Journal of the American Dietetic Association, 38: 334, April, 1961. 6E. N. Rathbun and N. Pace, "Body Composition I," QQurnal of Biological Chemistry, 158:675, 1945. 56 Table VIII. Predicted and determined specific gravity, per cent fat of body weight, kilograms of fat, per cent fat-free weight of body weight and kilo- grams of fat-free body weight NORMAL WEIGHT Characteristic Mean S.D. Median Range Predicted specific 1.0407 .0045 1.0394 1.0350 - gravity 1.0508 Per cent fat of 28.65 .469 29.37 23.58 body weight 31.64 Kilograms fat 16.98 .294 17.00 12.24 - 19.69 Per cent fat-free 71.35 .469 70.63 68.36 - body weight 76.43 Kilograms fat-free 42.079 276 41.92 38.04 - body weight 45.53 Determined 1 0260 0867 1.0262 1.0039 - specific gravity 1.0456 Per cent fat of 36.46 .447 36.23 26.18 - body weight 48.26 Kilograms fat 21.56 .737 22.26 14.99 - 28.82 Per cent fat—free 63.34 .257 63.77 51.74 - body weight 73.82 Kilograms fat-free 38.69 .372 38.59 28.48 - weight 54.54 57 UNDE RWE IGHT OVE RWEIGHT Mean S.D. Median Range Mean S.D. Median Range 1.0503 .0045 1.0508 1.0395— 1.0177 .0071 1.0175 1.0395- 1.0589 23.85 2.674 23.58 19.54- 40.78 4.126 40.86 19.54- 29.32 29.32 11.69 2.467 11.22 8.41- 33.32 6.068 34.18 8.41- 17.44 12.40 76.154 2.674 76.42 -70.68- 59.22 4.124 59.14 71.55- 80.47 80.47 36.99 3.429 37.10 30.24— 48.01 2 606 47.55 30.24- 42.67 42.67 1 0349 .0093 1.0304 1.0242— 9429 .0444 1.0078 .9963- 1.0542 1.0314 30.77 5.940 34.03 17.89- 44.65 6.274 46.13 33.53— 37.30 52.47 14.94 3.240 15.04 10.24- 36.63 6.625 36.69 24.91- 20.41 47.20 69.23 5.937 65.97 62.71— 55.13 6.537 53.82 46.38— 82.11 66.47 33.74 5.346 32.17 28.70— 45.12 4.945 45.21 33.87- 48.97 55.43 58 As seen in Table VIII the mean values for per cent fat of body weight were higher when calculated using the deter- mined specific gravity figures as compared to the mean values for specific gravity when the prediction formula was used.' A comparison was made in Table IX between the mean values obtained for determined and predicted specific gravity in the normal weight group with those values obtained in the Young Study for determined specific gravity. It was noted from the data in Table IX that a close proximity existed between the mean values obtained from predicted specific gravity in the present study and the mean values obtained by determined specific gravity in the Young study. The mean per cent fat of body weight in the normal weight group was 28.65 while in the Young study the mean value was 28.69. There was considerable variance between the mean values for per cent fat of body weight calculated using the deter- mined specific gravity figures as compared with the deter- mined specific gravity figures in the Young study. The mean value for per cent fat calculated from determined specific gravity in the normal weight group was 36.46 as compared ..u 59 Table IX. Comparison of mean values obtained from specific gravity measurements in the Young study with those in the present study Characteristics Mean S.D. Median Range Young Studv* % standard weight 98.93 8.61 97.4 83.2 - 128.0 Specific gravity 1.0408 0.0094 1.0411 l.0217-1.0665 %’body fat** 28.69 4.856 8.55 15.81 - 38.62 Kg. fat 16.91 -— -- -- %»fat-free weight 71.76 9.099 70.41 56.10 - 96.33 Kg. fat-free weight 42.15 6.073 41.18 31.94 - 61.11 Present Study Determined Specific Gravity (Normal Weight Group) %.standard weight 99.38 5.01 99.26 90.63 -108.71 Specific gravity 1.0260 .0867 1.0262 1.0039-1.0456 %’body fat 36.46 7.447 36.23 26.18 - 48.26 Kg. fat 21.56 4.737 22.26 14.99 - 28.82 %'fat-free weight 63.34 7.257 63.77 51.74 - 73.82 Kg. fat-free weight 38.69 6.372 38.59 28.48 - 54.54 Predicted Specific Gravity (Normal Weight Group) Specific gravity 1.0407 .0045 1.0394 1.0350-1.0508 % body fat 28.65 2.469 29.37 23.58 - 31.64 Kg. fat 16.98 2.294 17.00 12.24 - 19.69 % fat-free weight 71.35 2.469 70.63 68.36 - 76.43 Kg. fat-free weight 42.079 2.276 41.92 38.04 - 45.53 *Charlotte Young et al., op. cit., p. 106, reported on 94 normal weight subjects. **Rathbun and Pace, 10c. cit. 60 to a per cent fat mean of 28.69 in the Young study. There was a 6.46 per cent fat difference between the two means. Young and associates correlated the determined and pre- dicted specific gravities and found a correlation of .6990 between the two measurements.7 A similar correlation was run on the predicted and de- termined specific gravities obtained in the present study. The results are presented in Table X. Table X. Correlation coefficient between predicted and determined specific gravities Variables M N r Predicted specific gravity 43507.0357 45 .6772 Determined specific gravity 62580.4510 45 The coefficient correlation of .6772 between predicted and determined specific gravities in the present study com- pared favorably with the coefficient correlation of .6990 obtained in the Young study. 7Charlotte Young et al., "Predicting Specific Gravity and Body Fatness in Young Women," Journal of the American Dietetic Association, 40:107, February, 1962. 61 Energy Expenditure Energy Expenditure under Resting Conditions As indicated in Table XII the overweight group showed the largest mean caloric expenditure per hour (74.21), while the normal weight group (63.51), and underweight group (64.80), were closer in mean values for expenditure per hour. When calories per hour per square meter of surface area were computed the underweight group had the highest mean value of 42.45, followed by the overweight group with 38.57. The normal weight group had the lowest mean value with 38.42 calories per hour per square meter of surface area. The statistical tool used to test the null hypothesis that there were no significant differences between the groups in their caloric expenditures per hour per square meter of surface area was the F ratio, significant at the .05 level of confidence. The results of the test are pre- sented in Table XI. 62 Table XI. Analysis of variance of caloric expenditure per hour per square meter of surface area in the three weight groups Source Sum of Degrees Mean F Signi- of Squares of Square Ratio ficance Variance Freedom Total 1916.7937 44 Group 128.2674 2 64.1337 1.5061 N.S. Error 1788.5263 42 42.5840 The F ratio was not found to be significant and therefore, the null hypothesis was accepted. The results indicate that the differences between the groups in the caloric expenditure per hour were reduced to insignifi- cance when a correction was made for size of the square meter of surface area. The mean caloric expenditure per hour per kilogram of body weight was highest in the underweight group (1.3313), followed by the normal weight group (1.0792). The over- weight group showed the lowest mean caloric expenditures per hour per kilogram of body weight (.9081). The overweight group also had the largest oxygen intake with a mean of .2578 liters per minute. The underweight 63 group was next with .2228 liters per minute. The normal weight group had the lowest oxygen intake with a mean of .2192 liters per minute. The analysis of data indicated that the mean caloric expenditure under resting conditions was dependent upon body size. Also, when a correction was made for body size in terms of square meters of surface area, there were no statistically significant differences between the three weight groups. Energy Expenditure During Low Intensity Steady State Work Caloric expenditure during the steady state work was calculated on the basis of the exercise intensity for ten minutes of work. The work consisted of a walk on the treadmill at two miles per hour up a four per cent grade. When caloric expenditure per hour per kilogram of body weight was calculated the underweight group showed the highest mean values (3.991), followed by the normal weight group (3.784). The overweight group had the lowest mean caloric expenditure per kilogram of body weight (3.569). These results were similar to those obtained under resting conditions. 64 Table XII. Energy expenditure under resting conditions and NORMAL WEIGHT measurement Mean S.D. Median Range RESTING* Cal./hr./kg. body wt. 1.0792 .196 1.1214 .6125 - 1.4115 Cal./hr. 63.51 11.226 65.58 39.95 - 79.66 Ca1./hr./sq. meter 38.42 6.715 40.13 22.96 — 48.70 02/1./min./kg. .2192 .0378 .2268 .1391 - .2784 WORK** Ca1./hr./kg.*** 3.784 .4063 3.761 3.115 - body weight 4.416 Gross Cal./kg. body .833 .0867 .834 .687 - weight .974 Net Cal./kg. body .5058 .0677 .506 .352 - weight .637 02/1./min. .625 .0939 .6159 .4515 - .8020 02/1./min./kg. body .0106 .0047 .0104 .0075 - weight .0134 R.Q. .7926 .0440 .78 .73 - .90 Ventilation 86.42 17.776 80.80 64.74 — 140.43 Gross O2 debt 2.447 2.436 2.436 2.049 - 2.918 Net 02 debt .6923 .2345 .697 .235 - 1.069 Recovery R.Q. .8640 .0625 .85 .77 — 1.02 *Calculated on the basis of the average of two ten- minute resting gas samples. **Ca1cu1ated on the basos of the average of two five- minute low intensity steady state gas samples. 65 during low intensity steady state work UNDE RWEIGHT OVE RWEI GHT Mean S.D. Median Range Mean S.D. Median Range 1.3313 .244 1.385 .8506 - .90813 .098 .8904 .7011 - 1.744 1.1277 64.80 12.747 67.81 34.1 - 74.21 10.063 72.57 60.60 - 77.37 94.34 42.45 7.732 44.12 25.65 - 39.57 4.764 40.54 30.45 - 55.29 49.39 .2228 .0443 .2323 .1176 - .2578 .0332 .2540 .2100 - .2709 .3267 3.991 .4130 3.998 3.246 - 3.569 .2629 3.593 3.005 - 4.888 4.146 .893 .0966 .9069 .7031 - .768 .0557 .7732 .6364 — 1.019 .8908 .4941 .0822 .4771 .3718 - .495 .0491 .5002 .4260 - .6404 .5927 .4814 .0787 .4651 .3824 - .841 .0883 .8384 .7261 - 1.6234 1.0643 .0102 .0002 .0098 .0080 - .0103 .0036 .0104 .0088 — .0137 .0124 .8020 .0583 .81 .71 - .7606 .185 .77 .69 - .89 .86 79.32 1.770 76.42 54.42 105.81 12.21 102.91 90.00 — 124.07 120.72 2.262 .3834 2.235 1.619 — 2.900 .031 2.935 2.341 - 2.979 3.162 .4794 .2427 .537 .063 .8377 .1903 .870 .546 - .837 1.126 .858 .1005 .85 .71 - .8098 .0309 .84 .68 — 1.15 1.04 *Ca1./hr./kg. body weight is the actual work intensity during the ten—minute work period. 66 The statistical tool used to test the null hypothesis that there were no differences between the groups in cal- oric expenditure per hour per kilogram of body weight was the F ratio, significant at the .05 level of confidence. The results of the test are presented in Table XIII. Table XIII. Analysis of variance of caloric expenditure per hour per kilogram of body weight in the three weight groups Source Sum of Degrees Mean F Signi- of Squares of Square Ratio ficance Variance Freedom Total 6.9782 44 Group 1.3350 2 .6675 4.97 .05 Error 5.6432 42 .1344 The F ratio showed significance at the .05 level of confidence and therefore the null hypothesis was rejected. The alternate hypothesis, that there was significant dif- ferences between the groups in caloric expenditure per hour per kilogram of body weight was accepted. The statistical tool used to determine whether the greatest variance occurred was the "t test" significant 67 at the .05 level of confidence. The results of the "t test" are presented in Table XIV. Table XIV. "t test" on caloric expenditure per hour per kilogram of body weight in the three weight groups Calories per Hour S' '- per Kilogram of Mean t Score D.F. fiiggie Body Weight Normal 3.784 vs. vs. Underweight 3.991 1.3756 28 N.S. Normal 3.784 vs. vs. Overweight 3.569 1.7028 28 N.S. Underweight 3.991 vs. vs. Overweight 3.569 3.5159 28 .02 The greatest difference as indicated by the "t test" occurred between the underweight and overweight groups, significant at the .02 level of confidence. When gross caloric cost per kilogram of body weight was computed the mean value for the underweight group was the largest (.893), followed by the normal group (.833). The gross caloric cost per kilogram of body weight was the lowest for the overweight group whose mean value was .768 68 The F ratio significant at the .05 level of confidence was used to test the null hypothesis that there were no significant differences between the groups in their gross caloric cost per kilogram of body weight. The results of the test are presented in Table XV. Table XV. Analysis of variance of gross caloric cost per per kilogram of body weight in the three weight groups S S ource um Degrees Mean F Signi- Of Of Of S uare Rat'o f' Variance Squares Freedom q l icance Total .3957 44 Group .1159 2 .6580 8.71 .01 Error .2798 42 .00666 The F ratio was significant at the .01 level of con- fidence. The null hypothesis was therefore rejected, and the alternate hypothesis that there were significant dif- ferences between the groups in gross caloric cost per kil- ogram of body weight was accepted. The "t test" significant at the .05 level of confidence was used to determine where the greatest variance occurred 69 in the gross caloric cost per kilogram of body weight. The results of the "t test" are presented in Table XVI. Table XVI. "t test" on gross caloric cost per kilogram of body weight in the three weight groups Gross Caloric Cost per Kilogram of Mean t Score D.F. fS1gn1- Body Weight 1c nce Normal .8332 vs. vs. Underweight .8930 1.7844 28 N.S. Normal .8332 vs. vs. Overweight .7680 2.8820 28 .02 Underweight .8930 vs. vs. Overweight .7680 4.9646 28 .01 The greatest variance occurred between the overweight and underweight groups. The results of this test may be explained by noting that there were no observable differences in the mean values between the groups in net caloric cost per kilogram of body weight. The computations for the net caloric cost per kilogram of body weight included the subtraction of the resting caloric cost from the gross caloric cost, 70 therefore, since the overweight group had the highest mean resting value in calories per hour this would tend to in- fluence the gross caloric cost and not the net caloric cost in kilograms of body weight. The overweight group exhibited the largest mean oxygen intake in liters per minute (.841) followed by the normal group (.626), with the lowest mean value shown by the under- weight group (.481). This difference in mean value between the groups dis— appeared when the oxygen intake in liters per minute per kilogram of body weight was calculated. The data collected during the low intensity steady state work indicated that body weight tended to influence the caloric expenditure. Influence of Fat-free Body Weight and Per Cent Fat on Energy Expenditure As seen in Table XVII when calories per hour per kilo— gram of body weight was calculated the overweight group showed the lowest mean expenditure of energy while the underweight group exhibited the highest mean for the three groups. 71 When fat-free body weight was substituted for the total body weight the overweight group showed the highest mean expenditure per hour per kilogram of fat-free body weight while the underweight group had the lowest mean value. Table XVII. Caloric expenditure per hour per kilogram of body weight and caloric expenditure per hour per kilogram of fat-free body weight Measurement Mean S.D. Median Range (Cal./hr./kg.) Body weight Normal 3.784 .406 3.761 3.115—4.416 Underweight 3.991 .413 3.998 3.246-4.888 Overweight 3.569 .263 3.593 3.005-4.146 Fat-free Body Wt. Normal 5.848 .728 5.955 4.416-7.081 Underweight 5.814 .822 5.785 3.953-7.l44 Overweight 6.537 .908 6.444 4.685-7.996 The F ratio significant at the .05 level of confidence was used to test the null hypothesis that there were no significant differences between the groups in caloric ex- Penditure per hour per kilogram of fat-free body weight. The results of the "t test" are presented in Table XVIII. 72 Table XVIII. Analysis of variance of calories per hour per kilogram of fat-free body weight in the three weight groups Source Sum of Degrees Mean F Signi- Of S uares Of S are Ratio ficance Variance q Freedom qu Total 33.4251 44 Group 3.9901 2 2.4951 3.6855 .05 Error 28.4350 42 .6770 The F ratio showed significance at the .05 level of confidence and therefore the null hypothesis was rejected. The mean values for the groups indicated that the differences occurred between the overweight group (6.537) and the under- weight group (5.814), and, the overweight group (6.537) and the normal weight group (5.848). The analysis of data indicated that the caloric expen— diture per unit of fat-free body weight during the low intensity steady state work tended to vary with the fat content of the body. Also, as the fat deposition in the body increased it tended to be accompanied by a proportion- ate amount of fat-free body weight. The results of this study confirmed the null hypothesis 73 that overweight and underweight persons do not differ from normal weight persons in their conversion efficiency of chemical energy to mechanical energy during a standardized work test. These results are in agreement with those of other investigators (McKee and Bolinger? and Passmore and Durning) in that there is no deviation from normal in the work efficiency of obese persons; and that energy expendi— ture is proportional to body weight. 8Wallace McKee and Robert Bolinger, "Caloric Expendi- ture of Normal and Obese Subjects During Standard Work Test," Journal of Applied Physiology, 15:197-200, March, 1960. 9R. Passmore and J. V. G. A. Durnin, "Human Energy Expenditure," Physiological Reviews, 35:801-840, 1955. CHAPTER V SUMMARY, CONCLUSIONS, AND RECOMMENDATION SUMMARY The purpose of this study was to determine whether there was a difference between normal weight, underweight, and overweight college women in their efficiency to con— vert chemical energy to mechanical energy during a stand- ardized work test. The fat and fat-free content of 15 overweight, 15 normal weight, and 15 underweight women were calculated from densiometrically determined specific gravity and predicted specific gravity. Energy expenditure was ob- tained under resting conditions and during low intensity steady state work, which consisted of a ten minute walk on a motor—driven treadmill at two miles per hour up a four per cent grade. Means, standard deviations, medians, and ranges were used for the physical description of the subjects. The F ratio and "t tests" were used to determine if there were statistically significant differences between the three weight groups. 74 7 5 CONCLUSIONS From the statistical analysis of the data, the fol- lowing conclusions were drawn: 1. There was less than .01 difference in the mean values of the normal weight group and the underweight group for per cent fat obtained using the per cent stand- ard weight derived from predicted weight in the Build and Blood Pressure Study, and that obtained from the Pryor Widtheweight Tables. The largest variance occurred in the overweight group with a .03 difference in fat con— tent. This variation might have been caused by the dif- ficulty which the examiner experienced in measuring the bi-iliac width of the subjects to obtain the predicted weight from the Pryor Width-weight Tables. 2. The mean values for per cent fat in the three weight groups were higher when calculated using the deter— mined specific gravity figures than the mean values for per cent fat when the prediction formula for specific gravity was used. 3. A close proximity existed between the mean values for per cent fat in the normal weight group obtained from 76 predicted specific gravity and the mean values for per cent fat obtained from determined specific gravity in the Young Study. 4. There was considerable variance between the mean values for per cent fat calculated using determined speci- fic gravity figures for the normal weight group and those obtained in the Ybung Study. 5. The coefficient correlation of .6772 obtained in the present study between predicted and determined speci- fic gravity compared favorably with the correlation (r - .6999) obtained in YOung Study between predicted and determined specific gravity. Energy Expenditure Under Resting Conditions 1. The mean caloric expenditure per hour was largest in the overweight group and lowest in the underweight group. 2. There were no statistically significant differences between the groups when calories per hour per square meter of surface area was calculated. 3. The analysis of data indicated that the caloric expenditure under resting conditions was dependent upon 77 'body size and when a correction for surface area was made the differences between the three weight groups were re— duced to insignificance. Energy Expenditure During Low Intensity Steady State Work 1. Significant differences at the .05 level of confi- dence was indicated between the three weight groups when caloric expenditure per hour per kilogram of body weight ‘was calculated. The results of the "t test” showed that the variance occurred between the overweight and under- ‘weight groups. 2. Significant differences at the .01 level of confi- dence was found between the three weight groups when gross caloric cost per kilogram of body weight was computed. The results of the ”t test" showed that the variance oc— curred between the overweight and underweight groups. 3. There were no observable differences in the mean values of the three weight groups when net caloric cost per kilogram of body weight was calculated. 4. The overweight group exhibited the largest mean oxygen intake in liters per minute, followed by the normal weight group. The lowest mean value occurred in the 78 underweight group. The differences between the groups disappeared when oxygen intake in liters per minute per kilogram of body weight was calculated. 5. The data collected during the low intensity steady state work seemed to indicate that body size influenced the caloric expenditure in the three weight groups. Influence of Fat-free Body weight and Per Cent Fat on Energy Expenditure 1. Significant differences at the .05 level of confi- dence was found between the groups when caloric expendi— ture per hour per kilogram of fat-free body weight was calculated. The mean values for the groups indicated that the difference occurred between the overweight and underweight groups, and, the overweight and normal weight groups. 2. The caloric expenditure per unit of fat-free body ‘weight during the low intensity steady state work tended to vary with the fat content of the body. 3. As the fat deposition in the body increased it tended to be accompanied by a proportionate amount of fat-free body weight. 79 4. Overweight and underweight persons do not differ from normal weight persons in their conversion efficiency of chemical energy to mechanical energy during a stand- ardized work test. RECOMMENDATION 1. With a large number of women at Michigan State University, randomly selected, it would be possible to establish norms for per cent fat in different weight and age groups. BI BLIOGRAPHY 80 BIBLIOGRAPHY Books American Medical Association. Handbook of Nutrition. Second edition. New York: Country Life Press Cor— poration, 1951. 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N. and Pace, N. ”Body Composition I," Journal of Biological Chemistry, 158:667-676, 1945. Seltzer, Carl. "Body Build and Oxygen Metabolism at Rest and During Exercise," American Journal of Physiology, 129:1-13, April, 1940. Skerlj, B., Brozek, J. and Hunt, E. "Subcutaneous Fat and Age Changes in Body Build and Body Form," American Journal of Physical Anthropology, 11:577-99, March- December, 1953. Von Dobeln, Wilhelm. "Maximal Oxygen Intake, Body Size, and Total Hemoglobin in Normal Man," Acta Physiologica Scandinavica, 38:193-99, September, 1957. Wang, Chi-Che, Strouse, Solomon, and Morton, Zelma. ”The Metabolism of Obesity. V. Mechanical Efficiency," Archives of Internal Medicine. 45:727-33, January- June, 1930. Welch, B. E., Riendeau, R. P., Crisp, C. E., and Isenstein, R. S. "Relationship of Maximal Oxygen Consumption to Various Components of Body Composition," Journal of Applied Physiology, 12:395-98, May, 1958. Young, Charlotte, Martine, Elizabeth, Tensuan, Rosalinda, and Blondin, Joan. "Body Composition of Young Women," Journal of the American Dietetic Association, 38:332- 40, April, 1960. . "Predicting Specific Gravity and Body Fitness in Young Women," Journal of the American Dietetic Associa- tion, 40:102-08, February, 1962. APPENDIX A RAW DATA ON PHYSICAL CHARACTERISTICS OF SUBJECTS, SPECIFIC GRAVITY, PER CENT FAT, AND ENERGY EXPENDITURE 84 85 Table XIX. Raw data on physical characteristics of subjects L ——‘ Sub- Age Height Height Weight Weight jects (yrs.) (in.) (cm.) (lbs.) (kg.) Normal 1 18.11 62.99 160.0 121.1 55.04 2 18.8 63.58 161.5 114.2 51.92 3 18.10 64.96 165.0 135.7 61.68 4 18.7 66.93 170.0 141.3 64.22 5 18.11 65.94 167.5 143.5 65.22 6 18.7 65.94 167.5 134.9 61.32 7 18.6 65.94 167.5 133.1 60.48 8 19.11 63.78 162.0 120.6 54.84 9 18.3 64.96 165.0 131.3 59.70 10 18.6 67.13 170.5 134.7 61.22 11 18.9 66.89 169.9 139.0 63.18 12 19.3 66.73 169.5 133.3 60.60 13 18.10 65.75 167.0 120.0 54.54 14 18.5 65.94 167.5 123.7 56.24 15 19.3 64.37 163.5 122.5 55.70 Overweight 1 18.6 65.35 166.0 184.1 83.66 2 18.11 68.50 174.0 180.2 81.90 3 18.11 66.97 170.1 190.2 86.44 4 18.4 60.43 153.5 188.2 85.54 5 18.6 63.78 162.0 167.8 76.26 6 18.5 65.55 166.5 205.7 93.50 7 18.8 66.34 168.5 202.1 91.80 8 67.13 170.5 177.0 80.44 18.9 86 Table XIX (Continued) Sub- Age Height Height Weight Weight jects (yrs.) (in.) (cm.) (lbs.) (kg.) Overweight cont. 9 18.5 67.72 172.0 164.5 74.76 10 19.1 63.19 160.5 141.5 64.30 11 18.6 70.83 154.5 179.3 81.50 12 18.1 62.60 159.0 197.9 89.96 13 19.4 62.40 158.5 189.9 86.34 14 18.11 63.58 161.5 163.5 74.30 15 18.6 63.90 162.3 159.2 72.36 Underweight 1 18.1 62.60 159.0 103.0 46.80 2 18.10 61.02 155.0 88.2 40.10 3 18.11 69.88 177.5 116.0 52.72 4 18.4 67.72 172.0 131.2 59.64 5 18.2 66.93 170.0 110.0 50.00 6 18.6 64.17 163.0 98.5 44.76 7 19.5 67.91 172.5 105.3 47.86 8 19.0 60.24 153.0 92.2 41.90 9 18.11 66.73 169.5 130.9 59.48 10 19.4 66.54 169.0 103.9 47.22 11 18.8 66.14 168.0 112.9 51.30 12 19.0 67.72 172.0 104.9 47.66 13 19.7 67.72 172.0 107.6 48.90 14 18.4 61.02 155.0 96.2 43.74 15 18.6 65.95 167.5 106.0 48.18 87 Table XX. Raw data on surface area, chest width, bi-iliac width Sub- Surface Area Chest Bi-iliac jects Square Meters Width* Width* Normal 1 1.57 25.2 28.5 2 1.53 26.1 27.0 3 1.67 28.0 28.5 4 1.75 29.7 28.9 5 1.74 26.6 31.1 6 1.69 26.8 30.2 7 1.68 25.5 28.2 8 1.57 27.0 27.5 9 1.66 25.0 26.0 10 1.71 27.7 28.3 11 1.73 27.6 30.2 12 1.69 29.1 28.2 13 1.60 25.5 26.9 14 1.63 26.5 28.7 15 1.58 26.5 28.7 Overweight 1 1.91 29.3 30.0 2 1.96 31.7 30.8 3 1.99 30.4 30.8 4 1.82 30.2 31.5 5 1.80 28.5 30.3 6 2.01 31.1 31.5 7 2.02 30.3 33.5 8 1.95 30.1 29.3 Table xx (Continued) 88 Sub- Surface Area Chest Bi-iliac jects Square Meters Width* Width* Overweight (cont.) 9 1.87 28.6 28.1 10 1.67 25.2 27.3 11 1.79 35.5 32.0 12 1.91 30.2 31.5 13 1.87 31.9 31.5 14 1.78 26.9 28.7 15 1.77 29.2 28.3 Underweight 1 1.45 24.4 25.8 2 1.33 24.1 23.9 3 1.65 26.2 27.8 4 1.69 28.4 30.1 5 1.57 24.5 27.2 6 1.45 25.6 25.3 7 1.56 25.7 30.0 8 1.34 26.7 24.6 9 1.68 29.4 29.9 10 1.53 25.8 29.5 11 1.57 25.9 27.8 12 K 1.55 24.4 25.8 13 1.57 25.7 26.7 14 1.38 22.3 27.3 15 1.52 25.2 25.3 *Helen Pryor, Width-Weight Tables (second edition; California: Stanford University Press, 1940), PP- 1-2. 89 Table XXI. Raw data on predicted body weight and per cent of standard weight Sub- Predicted Per Cent Predicted Per Cent . Weight* Standard Weight** Standard JeCts (lbs.) Weight* (lbs.) Weight** Normal . l 127 95.35 122 99.26 2 123 92.85 126 90.63 3 141 96.24 129 105.19 4 144 98.13 136 103.90 5 144 99.65 132 108.71 6 141 95.67 132 102.20 7 133 100.08 132 100.83 8 122 98.85 126 95.71 9 123 106.75 129 101.78 10 144 93.54 136 99.04 11 142 97.89 136 102.21 12 143 93.22 136 98.01 13. 128 93.75 132 90.91 14 132 93.71 130 95.15 15 124 98.79 126 97.22 Overweight l 148 124.39 131 140.53 2 154 117.01 142 126.90 3 154 123.51 136 139.85 4 139 135.40 111 169.55 5 146 114.93 126 133.17 6 147 139.93 130 158.23 7 156 129.55 132 153.11 90 Table XXI (Continued) Sub- Predicted Per Cent Predicted Per Cent 'ects Weight* Standard Weight** . Standard 3 (lbs.) Weight* (lbs.) Weight** Overweight cont. 8 149 118.79 136 130.15 9 139 118.35 140 117.50 10 122 115.98 122 115.98 11 147 121.97 115 155.91 12 143 138.39 120 164.92 13 146 130.07 118 160.93 14 129 126.74 120 136.25 15 139 114.53 126 126.35 Underweight l 118 87.29 120 85.83 2 103 85.63 115 76.70 3 139 83.45 149 77.85 4 153 85.75 140 93.71 5 130 84.62 136 72.43 6 119 82.77 126 78.17 7 143 73.64 140 75.21 8 109 84.59 111 83.06 9 151 86.69 136 96.25 10 140 74.21 136 76.40 11 133 84.89 132 85.53 12 125 83.92 138 76.01 13 129 83.41 138 77.97 14 115 83.65 115 83.65 15 123 86.18 132 80.30 *Predicted weight determined by Pryor WidthéWeight Tables. **Predicted weight determined by Build and Blood Pressure Study, Society of Actuaries, 1959. 91 Table XXII. Raw data on skin fold fat measurements* Sub- Tri- Lower Umbil— . ceps Scapula Ribs Waist icus Pubis Sum JeCt (cm.) (cm.) (cm.) (cm.) (cm.) (cm.) (cm.) Normal 1 16.6 19.0 20.6 18.6 21.6 45.0 138.4 2 16.3 8.6 8.0 9.0 7.3 16.0 65.2 3 13.6 13.6 12.6 13.7 17.3 33.0 103.8 4 19.6 19.6 18.6 15.6 17.3 32.3 123.0 5 25.0 12.3 14.0 20.0 20.6 32.3 124.2 6 13.6 14.3 13.0 18.3 21.3 44.0 124.5 7 17.6 10.3 12.3 16.3 19.6 43.0 119.1 8 14.3 8.6 8.0 9.6 12.6 18.0 71.1 9 13.6 10.0 16.2 13.0 14.0 24.6 91.4 10 17.6 9.6 15.3 14.6 19.6 26.0 102.7 11 7.0 9.3 8.0 12.6 17.0 38.0 91.9 12 18.6 16.0 20.0 21.0 28.0 36.6 140.2 13 18.6 9.6 9.0 14.0 15.3 22.0 88.5 14 17.6 9.3 15.6 16.3 19.3 40.0 118.1 15 22.3 8.3 10.0 11.3 17.3 36.6 105.8 Overweight 1 34.3 25.0 35.6 38.3 34.3 54.6 222.1 2 31.6 28.3 23.0 34.0 32.0 54.6 203.5 3 30.6 27.2 33.6 34.4 30.5 60.6 216.9 4 36.6 32.3 37.6 43.0 44.6 50.0 244.1 5 30.6 20.6 30.6 23.6 28.0 47.0 180.4 6 35.5 29.0 40.6 27.6 33.0 58.6 224.3 7 37.6 31.0 48.6 43.6 47.3 53.3 261.4 8 34.0 26.0 40.0 43.0 35.0 51.6 229.6 92 Table XXII (Continued) Sub- Trl- Scapula Lower Waist UWbll‘ Pubis Sum 'ect ceps Ribs icus 3 (cm-) (cm.) (cm.) (cmw) (cmm) (cm.) (cm.) Overweight (cont.) 9 23.0 16.0 28.6 29.0 31.0 53.3 180.9 10 23.0 19.6 23.6 22.0 24.3 34.6 147.1 11 44.0 34.0 42.6 39.0 45.0 60.6 265.2 12 44.0 45.3 48.3 47.3 53.0 54.6 292.5 13 30.3 39.6 46.0 46.6 38.3 60.3 261.1 14 28.0 16.6 14.3 21.0 22.3 49.0 151.2 15 26.0 25.3 26.0 25.3 33.6 52.0 188.2 Underweight 1 12.0 10.3 8.6 19.0 15.0 29.7 94.6 2 6.6 6.3 7.6 10.6 15.3 32.0 78.4 3 11.6 10.0 7.3 7.3 15.6 15.3 67.1 4 10.6 7.0 6.3 8.0 12.3 36.3 80.5 5 9.0 6.6 8.3 10.6 17.3 30.6 82.4 6 12.6 8.0 5.3 9.0 15.0 24.6 74.5 7 4.6 6.3 5.0 4.0 12.3 23.3 55.5 8 8.3 7.0 7.0 6.3 9.6 5.6 43.8 9 15.3 12.6 10.0 13.3 16.3 38.2 105.7 10 8.6 7.0 6.6 12.6 14.0 25.6 74.4 11 18.0 12.3 10.6 12.3 16.3 23.0 92.5 12 6.6 7.3 7.3 8.0 7.3 8.6 45.1 13 7.3 6.6 7.6 13.0 11.3 23.3 69.1 14 17.0 7.3 9.3 15.6 13.3 29.6 92.1 15 12.3 11.6 9.0 12.6 15.6 25.3 86.4 Ennd with the average of three determined. *Calculated on the basis of 3 measurements in each site 93 Table XXIII. Raw data on predicted specific gravity, per cent fat of body weight, kilograms of fat, per cent of fat—free body weight, and kilograms of fat- free body weight in normal weight group Sub— Body Predicted Fat % Fat % Fat Fat—free , Weight Spec1f1c Body (kg.) Free Body Wt. jeCt (kg.) Gravity* Weight** Weight (kg.) Normal 1 55.04 1.0376 30.30 16.68 69.69 38.36 2 51.92 1.0500 23.98 12.45 76.02 39.47 3 61.68 1.0417 28.19 17.39 71.81 44.29 4 64.22 1.0414 28.34 18.20 71.66 45.02 5 65.22 1.0408 28.65 18.69 71.34 46.53 6 61.32 1.0372 30.50 18.70 69.50 42.62 7 60.48 1.0362 31.02 18.76 68.98 41.72 8 54.84 1.0474 25.29 13.87 74.71 40.97 9 59.70 1.0434 27.31 16.30 72.70 43.40 10 61.22 1.0456 26.20 16.04 73.80 45.18 11 63.18 1.0390 29.57 18.68 70.43 44.50 12 60.60 1.0412 28.45 17.24 71.55 43.36 13 54.54 1.0472 25.39 13.85 74.60 40.69 14 56.24 1.0396 29.27 16.46 70.73 39.78 15 55.70 1.0393 29.47 16.41 70.54 39.29 *Predicted specific gravity calculated from Young et al., "Predicting Specific Gravity and Body Fatness in Young Women," Journal of the American Dietetic Association, 40: 105, February, 1962. Using Pryor Width4Weight Tables for standard weight. **Per cent body fat of body weight calculated Rathbun and Pace, "Body Composition," Journal of Biological Chemis- try, 158:675, 1945. Table XXIII (Continued) 94 Sub- Body Predicted Fat % Fat % Fat Fat-free , Weight Specific Body (kg.) Free Body Wt. jeCt (kg.) Gravity* Weight** Weight (kg.) Normal 1 55.04 1.0356 30.88 17.00 69.11 38.04 2 51.92 1.0508 23.58 12.24 76.43 39.68 3 61.68 1.0387 29.73 18.34 70.27 43.34 4 64.22 1.0394 29.37 18.86 70.63 45.36 5 65.22 1.0378 30.19 19.69 69.81 45.53 6 61.32 1.0350 31.64 19.40 68.36 41.92 7 60.48 1.0359 31.17 18.85 68.83 41.63 8 54.84 1.0482 24.80 13.60 75.20 41.24 9 59.70 1.0417 28.19 16.83 71.81 42.87 10 61.22 1.0437 27.17 16.63 72.84 44.59 11 63.18 1.0376 30.30 19.14 69.71 44.04 12 60.60 1.0396 29.27 17.74 70.73 42.86 13 54.54 1.0482 24.89 13.58 75.10 40.96 14 56.24 1.0391 29.52 16.60 70.48 39.64 15 55.70 1.0399 29.11 16.21 70.90 39.49 *Predicted specific gravity calculated from Young, cit. **Per cent body fat of body weight calculated from ”Body Composition," Journal of Biological 1945. Rathbun and Pace, 158:675, Chemis loc. Using Build and Blood Pressure Study standard weight. trv. 95 Table XXIV. Raw data on predicted specific gravity, per cent fat of body weight, kilograms of fat, per cent of fat-free body weight, and kilograms of fat- free body weight in underweight group Sub- Body Predicted Fat % Fat %»Fat Fat-free , Weight Specific Body (kg.) Free Body Wt. DeCt (kg.) Gravity* Weight** Weight (kg.) Underweight 1 46.80 1.0461 25.95 12.14 74.06 34.66 2 40.10 k,9457 26.15 10.49 73.84 29.61 3 52.72 1.0535 22.22 11.71 77.79 41.01 4 59.64 1.0439 27.07 16.14 72.94 43.50 5 50.00 1.0467 25.65 12.83 74.34 37.17 6 44.76 1.0498 24.08 10.78 71.39 33.98 7 47.86 1.0535 22.23 10.64 77.77 37.22 8 41.90 1.0573 20.33 8.52 79.67 33.38 9 59.48 1.0428 27.90 16.59 72.11 42.89 10 47.22 1.0523 22.83 10.78 77.17 36.44 11 51.30 1.0498 24.08 12.35 75.93 38.95 12 47.66 1.0562 20.88 9.95 79.12 37.71 13 48.90 1.0502 23.88 11.68 76.11 37.22 14 43.74 1.0474 25.39 11.06 74.71 32.68 15 48.18 1.0484 24.79 11.94 75.22 36.24 *Predicted specific gravity calculated from: Young et al., "Predicting Specific Gravity and Body Fatness in Young Women," Journal of the American Dietetic Association, 40: 105, February, 1962. Using the Pryor Width-Weight Tables for standard weight. **Per cent body fat of body weight calculated from: Rathbun and Pace, "Body Composition I," Journal of Bioloqi- cal Chemistry, 158:675, 1945. Table XXIV (Continued) 96 Body Predicted Fat % Fat % Fat Fat-free §Ub‘ Weight Specific Body (kg.) Free Body Wt. JeCt (kg.) Gravity* Weight** Weight (kg.) Underweight 1 46.80 1.0466 25.69 12.02 74.32 34.78 2 40.10 1.0488 24.59 9.86 75.41 30.24 3 52.72 1.0554 21.28 11.22 78.72 41.50 4 59.64 1.0412 28.45 16.97 71.55 42.67 5 50.00 1.0508 23.58 11.79 76.42 38.21 6 44.76 1.0514 23.28 10.42 76.72 34.34 7 47.86 1.0530 22.48 10.76 77.52 37.10 8 41.90 1.0578 20.08 8.41 79.93 33.49 9 59.48 1.0395 29.32 17.44 70.68 42.04 10 47.22 1.0516 23.18 10.95 76.81 36.27 11 51.30 1.0496 24.18 12.40 75.83 38.90 12 47.66 1.0589 19.54 9.31 80.47 38.35 13 48.90 1.0520 22.98 11.24 77.01 37.66 14 43.74 1.0474 25.29 11.06 74.71 32.68 15 48.18 1.0504 23.78 11.46 76.21 36.72 *Predicted specific gravity calculated from: Young, loc. cit., Using Build and Blood Pressure Study for standard weight. **Per cent body fat of body weight calculated from: "Body Composition I," Journal of Biologi- 1945. Rathbun and Pace, cal Chemistry, 158:675, 97 Table XXV. Raw data on predicted specific gravity, per cent fat of body weight, kilograms of fat, per cent of fat-free body weight, and kilograms of fat- free body weight in overweight group Sub- Body Predicted Fat % Fat % Fat Fat-free , Weight Specific Body (kg.) Free Body Wt. JeCt (kg.) Gravity* Weight** Weight (kg.) Overweight 1 83.66 1.0230 37.93 31.72 62.07 51.93 2 81.90 1.0255 36.60 29.98 63.39 51.92 3 86.44 1.0208 39.10 33.80 60.90 52.64 4 85.54 1.0212 38.88 33.26 61.12 52.28 5 76.26 1.0294 34.55 26.55 65.45 49.91 6 93.50 1.0160 47.09 44.03 52.91 49.47 7 91.80 1.0218 38.56 35.40 61.44 56.40 8 80.40 1.0262 36.30 29.20 63.70 51.24 9 74.76 1.0256 36.55 27.32 63.46 47.44 10 64.30 1.0343 32.00 20.58 67.99 43.72 11 81.50 1.0213 38.83 31.65 61.17 49.85 12 89.96 1.0179 40.64 36.56 59.36 53.40 13 86.34 1.0187 40.22 34.73 59.78 51.61 14 74.30 1.0246 37.08 27.55 63.92 46.75 15 72.36 1.0274 35.60 25.76 64.40 46.60 *Predicted specific gravity calculated from Young et al., "Predicting Specific Gravity and Body Fatness in Young Wo- men," Journal of the American Dietetic Association, 40:105, February, 1962. Using the Pryor Width-Weight Tables for standard weight. **Per cent body fat of body weight calculated from Rathbun and Pace, "Body Composition I," Journal of Biological Chemis- try, 158:675, 1945. 98 Table XXV (Continued) Sub- Body Predicted Fat % Fat % Fat Fat—free , Weight Specific Body (kg.) Free Body Wt. jeCt (kg.) Gravity* Weight** Weight (kg.) Overweight 1 83.66 1.0175 40.86 34.18 59.14 49.48 2 81.90 1.0221 38.40 31.45 61.60 50.45 3 86.44 1.0152 42.10 36.39 57.90 50.05 4 85.54 1.0096 45.12 38.60 54.87 46.94 5 76.26 1.0232 37.82 28.84 62.18 47.42 6 93.50 1.0098 45.02 42.09 54.98 51.41 7 91.80 1.0138 42.85 39.34 57.15 52.46 8 80.40 1.0223 38.30 30.81 61.70 49.63 9 74.76 1.0259 36.40 27.21 63.60 47.55 10 64.30 1.0343 32.00 20.58 67.99 43.72 11 81.50 1.0097 45.07 36.73 54.93 44.77 12 89.96 1.0092 45.34 40.79 54.66 49.17 13 86.34 1.0082 45.89 36.62 54.11 46.72 14 74.30 1.0213 38.83 28.85 61.17 45.45 15 72.36 1.0234 37.71 27.29 62.29 45.07 *Predicting specific gravity calculated from Young, loc. cit., Using the Build and Blood Pressure Study for standard weight. **Per cent body fat of body weight calculated from Rathbun and Pace, "Body Composition I," Journal of Biological Chemis- try, 158:675, 1945. Table XXVI. body weight, 99 Raw data on determined specific gravity, cent fat, kilograms of fat, per cent fat-free and kilograms of fat-free body weight in the three weight groups per Determined Fat % Fat % Fat Fat—free Specific Specific Body (kg.) Free Body Wt. Gravity Weight Weight (kg.) Normal 1 1.0039 48.26 26.56 51.74 28.48 2 1.0403 28.88 14.99 71.13 36.93 3 1.0456 26.18 16.15 73.82 45.53 4 1.0407 28.70 18.43 68.19 43.79 5 1.0193 39.90 26.02 60.10 39.20 6 1.0115 44.10 27.04 55.90 34.28 7 1.0050 47.65 28.82 52.35 31.66 8 1.0414 28.34 15.54 71.66 39.30 9 1.0410 29.05 17.34 70.95 42.36 10 1.0214 38.76 23.73 61.24 37.49 11 1.0272 35.69 22.55 64.31 40.63 12 1.0121 43.78 26.53 56.22 34.07 13 1.0262 36.23 19.76 63.77 54.54 14 1.0355 31.38 17.65 68.62 38.59 15 1.0192 39.97 22.26 60.04 33.44 Underweight 1 1.0542 21.87 10.24 78.12 36.56 2 1.0454 26.30 10.55 73.57 29.55 3 1.0412 28.44 14.99 71.57 37.73 4 1.0333 17.89 10.67 82.11 48.97 5 1.0273 35.65 17.83 64.34 32.17 6 1.0304 34.03 15.23 65.99 29.53 7 1.0255 36.59 17.51 63.41 30.35 100 Table XXVI (Continued) Determined Fat % Fat % Fat Fat-free Specific Specific Body (kg.) Free Body Wt. Gravity Weight Weight (kg.) Underweight (cont.) 8 1.0423 27.88 11.69 72.10 30.21 9 1.0299 34.32 20.41 65.69 39.07 10 1.0242 37.30 17.61 62.71 29.61 11 1.0271 35.76 18.34 64.25 32.96 12 1.0471 25.42 12.12 74.57 35.54 13 1.0383 29.95 14.65 70.04 34.25 14 1.0297 34.38 15.04 65.61 28.70 15 1.0272 35.72 17.21 64.28 30.97 Overweight 1 1.0017 49.48 41.39 50.53 42.27 2 1.0102 44.80 36.69 55.20 45.21 3 1.0269 35.88 31.01 64.13 55.43 4 1.0078 46.13 39.50 53.82 46.04 5 1.0265 36.07 27.51 63.93 48.75 6 .9963 50.40 47.12 46.38 49.60 7 1.0039 48.25 44.29 51.75 47.51 8 1.0119 43.90 35.30 56.09 45.10 9 1.0203 39.39 29.45 60.61 45.31 10 1.0056 47.32 30.43 52.67 33.87 11 .9998 50.51 41.17 49.48 40.33 12 .9963 42.47 47.20 47.53 42.76 13 .9975 51.81 44.73 48.19 41.61 14 1.0314 33.53 24.91 66.47 49.39 15 1.0195 39.82 28.81 60.19 43.55 101 Table XXVII. Raw data collected under resting conditions. Calories per hour, calories per hour per square meter of surface area, oxygen intake in liters per minute, and calories per hour per kilogram of body weight Ca1./hr./ Cal./hr./kg. Subject Cal./hr. sq. meter 02 l./min. Body Weight Normal 1 45.75 29.14 .1576 .8312 2 62.52 40.86 .2220 1.2042 3 69.17 41.42 .2350 1.1214 4 65.58 37.47 .2268 1.0312 5 39.95 22.96 .1391 .6125 6 67.49 39.93 .2334 1.1006 7 67.41 40.13 .2310 1.1146 8 65.52 41.73 .2246 1.1947 9 79.66 47.99 .2696 1.3343 10 57.07 33.37 .1969 .9322 11 72.20 41.73 .2460 1.1428 12 70.88 41.94 .2426 1.1696 13 55.14 34.47 .1948 1.0110 14 79.38 48.70 .2784 1.4115 15 54.97 34.79 .1916 .9869 Overweight 1 94.34 49.39 .3267 1.1277 2 74.60 38.06 .2540 .9109 3 60.60 30.45 .2100 .7011 4 83.77 46.03 .2843 .9793 5 73.05 40.58 .2598 .9579 6 81.81 40.70 .2805 .8750 102 Table XXVII (Continued) Subject Ca1./hr. ::T°;::é: 02 l./min. g:;§/;:ig:3' Overweight (cont.) 7 85.66 42.41 .2936 .8786 8 79.22 40.63 .2718 .9848 9 64.34 34.41 .2270 .8606 10 63.91 38.27 .2224 .9939 11 72.57 40.54 .2581 .8904 12 71.43 37.40 .2540 .7940 13 81.67 43.67 .2852 .9459 14 61.79 34.71 .2134 .8316 15 64.42 36.40 .2269 .8903 Underweight 1 54.73 37.74 .1834 1.1694 2 34.11 25.65 .1176 .8506 3 76.74 46.51 .2677 1.4556 4 65.85 38.96 .2257 1.1041 5 69.27 44.12 .2345 1.3854 6 40.70 28.07 .1410 .9093 7 67.81 43.47 .2348 1.4168 8 64.52 48.15 .2237 1.5399 9 77.37 46.05 .2666 1.3008 10 72.86 47.62 .2475 1.5430 11 67.12 42.75 .2318 1.3084 12 68.56 44.23 .2323 1.4385 13 61.57 39.22 .2140 1.2591 14 76.30 55.29 .2709 1.7444 15 74.43 48.97 .2507 1.5448 103 Table XXVIII. Raw data collected during low intensity steady state work. Oxygen liters per minute and oxygen liters per minute per kilogram of body weight Subject O2 1./min. Ogééy/Siightg. Normal 1 .6159 0.0112 2 .5332 0.0103 3 .8020 0.0130 4 .5908 0.0092 5 .7015 0.0108 6 .6597 0.0108 7 .4515 0.0075 8 .5375 0.0098 9 .6874 0.0115 10 .7324 0.0112 11 .6433 0.0102 12 .5442 0.0090 13 .7299 0.0134 14 .5850 0.0104 15 .5720 0.0103 Overweight 1 .7845 0.0094 2 .7732 0.0094 3 .7570 0.0088 4 .9438 0.0110 5 .8235 0.0108 6 .8688 0.0093 104 Table XXVIII (Continued) I o OZ/lO/mino/kg. S O . . . ubject 2 1 /m1n Body Weight Overweight (cont.) 7 .9373 0.0102 8 .7261 0.0090 9 .8384 0.0112 10 .7970 0.0124 11 .8685 0.0107 12 1.0643 0.0119 13 .8484 0.0098 14 .8376 0.0113 15 .7493 0.0104 Underweight l .5581 0.0119 2 .4970 0.0124 3 .4599 0.0137 4 .4777 0.0080 5 .6234 0.0125 6 .4928 0.0110 7 .4088 0.0085 8 .4350 0.0104 9 .6574 0.0111 10 .4651 0.0099 11 .5005 0.0098 12 .4311 0.0090 13 .3890 0.0080 14 .3824 0.0087 [—1 U1 .4441 0.0092 105 Table XXIX. Raw data collected during low intensity steady state work. Respiratory quotient, ventilation, gross oxygen debt, net oxygen debt and recovery respiratory quotient Sub- Venti- Gross Net Recov- . R.Q. lation Oxygen Oxygen ery JeCt (1.) Debt (1.) Debt (1.) R.Q. Underweight l .82 76.16 2.135 .668 .85 2 .76 54.42 1.619 .678 .80 3 .71 106.45 2.979 .837 .80 4 .74 67.65 2.014 .208 .80 5 .84 124.07 2.556 .680 .92 6 .78 61.53 1.774 .646 .92 7 .81 76.42 2.235 .357 .84 8 .71 64.45 2.238 .448 .71 9 .86 78.54 2.888 .755 .87 10 .79 73.51 2.517 .537 .87 11 .88 82.76 2.193 .339 .79 12 .89 83.99 2.413 .555 1.15 13 .76 69.33 1.770 .067 .76 14 .82 92.15 2.230 .063 .90 15 .86 78.33 2.359 .353 .89 Normal 1 .83 76.08 2.049 .788 .89 2 .73 73.08 2.248 .472 .83 3 .85 140.43 2.918 1.038 1.02 4 .82 80.80 2.622 .808 .89 5 .77 69.34 2.182 1.069 .92 6 .79 90.78 2.549 .682 .81 Table XXIX (Continued) 106 Sub— Venti- Gross Net Recov- . R.Q. lation Oxygen Oxygen ery JeCt (1.) Debt (1.) Debt(l.) R.Q. Normal (Cont. 7 .77 78.22 2.083 .235 .85 8 .76 64.74 2.436 .639 .77 9 .78 97.59 2.905 .748 .91 10 .75 84.10 2.484 .909 .78 11 .82 97.01 2.665 .697 .90 12 .90 82.76 2.412 .471 .85 13 .76 92.36 2.357 .799 .81 14 .79 89.16 2.587 .360 .88 15 .77 79.80 2.203 .670 .85 Overweight 1 .69 95.54 3.162 .548 .80 2 .79 96.36 2.953 .921 .84 3 .81 96.99 2.341 .661 .97 4 .79 124.48 3.369 1.095 .87 5 .68 100.03 2.869 .791 .68 6 .86 115.59 2.790 .546 1.04 7 .83 130.72 3.092 .743 .93 8 .82 95.40 2.825 .651 .99 9 .75 90.00 2.942 1.126 .84 10 .77 110.85 2.650 .871 .84 ll .67 105.54 2.935 .870 .76 12 .67 106.17 3.121 1.089 .75 13 .73 112.91 3.073 .791 .77 14 .78 102.91 2.540 .833 .86 15 .77 98.68 2.845 1.030 .84 107 Table XXX. Raw data collected during low intensity steady state work. Calories per hour per kilogram of body weight. Calories per hour per kilogram of fat-free body weight, gross caloric cost per kilogram of body weight and net caloric cost per kilogram of body weight Sub- Cal./Hr./ Ca1./Hr./ Gross Cal. Net Cal. , Kg. Body Kg.Fat-free Cost/Kg. Cost/Kg. JeCt Weight Body Wt. Body Wt. Body Wt. Normal 1 3.664 7.0807 .7935 .544 2 3.855 5.4201 .8520 .491 3 4.412 5.9780 .9742 .637 4 3.318 4.8657 .7535 .447 5 3.216 5.3499 .7015 .518 6 3.860 6.9046 .8434 .513 7 3.115 5.9499 .6866 .352 8 3.630 5.0646 .8165 .458 9 4.237 5.9713 .9463 .546 10 3.890 6.3516 .8421 .562 11 3.761 5.8479 .8345 .491 12 3.602 6.4053 .7937 .443 13 4.416 4.4164 .9441 .587 14 4.225 6.1573 .9295 .506 15 3.575 5.9547 .7882 .492 Overweight 1 3.550 7.0267 .7732 .4348 2 3.276 5.9350 .7209 .4477 3 3.005 4.6849 .6364 .4260 4 3.758 6.9813 .8187 .5249 5 3.709 6.3019 .7944 .5071 6 3.419 6.4442 .7204 .4578 108 Table XXX (Continued) Sub- Ca1./Hr./ Cal./Hr./ Gross Cal. Net Cal. , Kg. Body Kg. Fat-free Cost/Kg. Cost/Kg. jeCt Weight Body Weight Body Wt. Body Wt. Overweight (Cont.) 7 3.653 7.0578 .7758 .4959 8 3.358 5.9887 .7364 .4411 9 3.620 5.9723 .7941 .5350 10 4.146 7.8699 .8908 .5927 11 3.593 7.2602 .7699 .5028 12 3.793 7.9962 .7967 .5581 13 3.466 7.1909 .7472 .4635 14 3.733 5.6158 .7888 .5394 15 3.463 5.7243 .7687 .5002 Underweight 1 4.169 5.3360 .9166 .5724 2 3.888 5.2759 .8418 .5867 3 4.838 6.7594 1.0775 .6404 4 3.246 3.9528 .7031 .3718 5 4.596 7.1439 1.0190 .6033 6 3.644 5.5236 .8035 .5306 7 3.669 5.7845 .8379 .4129 8 4.132 5.7302 .9391 .4771 9 4.169 6.3461 .9320 .5417 10 3.995 6.3709 .9291 .4662 11 3.998 6.2226 .8711 .4787 12 3.767 5.0507 .9014 .4700 13 3.477 4.9640 .7524 .3746 14 4.283 6.5270 .9648 .4424 15 3.999 6.2208 .9069 .4435 APPENDIX B FORMULAS AND CALCULATIONS USED TO COMPUTE SPECIFIC GRAVITY, PER CENT FAT, FAT-FREE BODY WEIGHT, AND ENERGY EXPENDITURE 109 METABOLIC CALCULATIONS Subject Height A. RESTING Date Weight (1) BAG #1 (Gas collected 10 min. Subject in reclining position) (a) R.Q. = (b) Ventilation (c) Liters O 2 (d) 02 intake = liters 1.07 uncorrected x Kofranyi ventilation correction _ liters temperature — corrected correction ventilation true 02 x ventilation 100 ' 0 liters 2 liters 02 = 10 min. liters/min. (e) Metabolic rate = liters/min x caloric equiv. x 60 min. = sq. m. cal./hr./sq. m 110 111 (2) BAG #2 (gas collected 10 min. Subject in reclining position) Calculations same as above. Cal./hr. = calculated on the average of the two resting samples. Ca1./hr./sq. m. = " O2 l./min. = " EXERCISE (1) BAG #1 (gas collected during first five minutes of a 10 minute walk of 2 miles per hour on a 4% grade) (a) R. Q. = (b) Ventilation = x uncorrected Kofranyi ventilation correction x = liters temperature corrected correction ventilation true 0 x ventilation . _ 2 (c) Liters 02 — 100 = liters 02. (d) 02 intake = liters 02 = 5 min. liters/min. 112 (e) Exercise intensity = 02 liters/min. x caloric equiv. x 60 min. kg. body weight Ca1./hr./kg. body weight (f) Net 02 intake = liters/min O2 intake - liters/min. = liters/min. resting equivalent (2) BAG #2 (gas collected during last five minutes of a 10 minute walk of 2 miles per hour on a 4% grade) Calculations same as above. Cal./hr./kg. body weight calculated on the average of the two exercise gas bags Ventilation = " O2 1./min./kg. body wt. = ” O2 l./min. = " R.Q. = " RECOVERY (l) BAG #1 (recovery for 8 minutes) (a) R.W. = 113 (b) Ventilation = x uncorrected Kofranyi ventilation correction = = liters temperature corrected correction ventilation true 02 x ventilation (c) Gross debt = 100 = liters 02 gross debt (d) Net oxygen , debt = liters O2 _ x 8 = resting 0 recovery resting intake time equiv. = liters net debt D. DERIVED MEASURES (1) Total oxygen (gross) = liters O2 Exercise Bag #1 + liters 02 Exercise Bag #2 liters O gross debt = _____iiters 114 (2) Oxygen requirement = liters (net) total oxygen - 1./min. x 18 = liters resting 0 time of resting intake runs + equivalent recovery liters (3) Caloric . . liters O . . . cost(gross) = 2 x cal equiv _ cal Exercise Bag #1 liters 02 x cal. equiv. cal. Exercise Bag #2 — + liters 02 x cal. equiv. _ cal. gross debt = gross calories (4) Caloric cost (net) = - ______.X gross . resting cal. equiv. cal. cost equiv. = calories 115 FORMULAS USED FOR PER CENT OF FAT OF BODY WEIGHT, KILOGRAMS OF FAT OF BODY WEIGHT, PER CENT OF FAT-FREE BODY WEIGHT, KILOGRAMS OF FAT- FREE BODY WEIGHT (1) PER CENT FAT OF BODY WEIGHT* 5.548 Per cent fat = 100 ————T—T—‘ — 5.044 speCific gravity (2) KILOGRAMS OF FAT OF BODY WEIGHT Kilograms fat = x per cent fat body weight (3) KILOGRAMS OF FAT-FREE BODY WEIGHT Kg. fat-free body wt. = _ body weight kg. fat (4) PER CENT FAT-FREE BODY WEIGHT _ kg. fat-free body weight A fat-free body wt. body weight *Rathbun and Pace, "Body Composition I," Journal of Chemistry, 158:674, 1945. 116 PREDICTION FORMULA FOR SPECIFIC GRAVITY* (1) Specific gravity = 1.0084 - .0004231 xl - .0003401 xl3 when x1 = skinfold on mid-abdominal line halfway be- tween the umbilicus and the pubis (in mm.) xl3 = percentage "standard" weight (average weight per height and age)** actual weight A standard weight = standard weight *Young et al., "Predicting Specific Gravity and Body Fatness in Young Women," Journal of the American Dietetic Associa— tion, 40:105, February, 1962. **Percentage standard weight used in this formula was calcu- lated on the basis of the predicted weight determined by the Society of Actuaries, "Build and Blood Pressure Study," Vol. I, 1959. (2) Determined specific gravity = weight in air (kg.) weight in air (kg.) - weight in water (kg.) - functional residual air r) (I‘ll-l s it'll. 93‘: HICHIGRN STRTE UNIV. LIBRARIES 31293010739799